Chemistry Grade - 10 (Science )

 

Chemistry           Grade -   10 (Science )

Unit                               Topics
7                                              Classification of Elements
8                                               Chemical Reaction
9                                              Acid, Base, and Salt
10                                            Some Gases (CO_2, NH₃)
11                                            Metals
12                                            Hydrocarbon and its Compounds
13                                            Materials used in Daily Life

                           Specification Grid  -2074 

 Division of 22 marks in Knowledge(K) ,Understanding(Un), Application(AP), and Higher abilities(HA) types of questions  

Areas	S.N.	Units	Total no. of questions & their marks					Remarks
			K-20%	Un-35%	Ap-24%	HA-21%	Total
Chemistry	7 8 9 10 11 12 13	Classification of Elements Chemical Reaction Acid, Base and Salt Some Gases (CO2, NH3) Metals Hydrocarbon &its Compounds Materials used in Daily Life	4x1= 4	4x2= 8	2x3= 6	1x4= 4	22 marks	Physics-56+ Chemistry-56+ Biolog-56+Geology &Astronomy-12 Periods=180 periods
	7		4	4	2	1	22 marks

Scholastic Areas  :-Grading on 9 points Scale

S.N.	Marks range	Grade	Attributes	Grade Points	Remarks
1 2 3 4 5 6 7 8 9	90 to 100 80 to below 90 70 to below 80 60 to below 70 50 to below 60 40 to below 50 40 to below 50 30 to below 40 0 to below 20	A+ A B+ B C+ C D+ D E	Outstanding Excellent Very good Good Satisfactory Acceptable Partially Acceptable Insufficient Very insufficient	4.0 3.6 3.2 2.8 2.4 2.0 1.6 1.2 0.8	The minimum qualifying grade in all subjects under scholastic Domain Is C

    Unit:-7    Classification of elements

Periodic table :A table in which elements are classified into various blocks ,periods, and groups on the basis of their similarities and dissimilarities is called periodic table .There are two types lines in the periodic table :

i)Group :The vertical columns of periodic table are called groups .The valence electrons of all elements in the same groups are the  same .The size of atoms increases from top to the bottom in the group of periodic table .

ii)Periods :The horizontal rows of periodic table are called periods .The valence electrons of the elements and the size of atoms increases from left to right in periodic table .

Advantages of periodic table:

i)it help to remember the properties of elements, if its position in the periodic table is known .

ii)It makes the study of chemistry systematic and easy .

iii)It is used as teaching aids in chemistry in school and college .

A.)Mendeleev`s periodic table : The periodic table in which elements are arranged in the table with the increasing order of their atomic weight is called Mendeleev’s periodic table .It was formed by Demitri Mendeleev’s .

Mendeleev’s periodic law: It states that the physical and chemical properties of elements are periodic functions of their atomic weights .

Advantages of Mendeleev’s periodic table :

i)Mendeleev’s periodic table divided the elements into horizontal rows called periods and vertical columns are called groups .

ii)It help to correct the incorrect atomic weights .

iii)Mendeleev’s left proper gaps in the periodic table for undiscovered elements .

iv)There are 8 groups numbered from I  to vii.

v)Physical and chemical properties of the elements are periodic function of their atomic weight .

Drawbacks of Mendeleev’s periodic table :

i)The position of hydrogen could not be explained by Mendeleev’s periodic table i.e. Hydrogen resembles metal as well halogens .

ii)There was not suitable place for lanthanides and actinides    series in the Mendeleev’s periodic table .

iii)Copper ,Gold and silver and alkali metals both were placed in the same groups .

iv) Some elements having higher atomic weight but have been placed before element of lower atomic weights i.e. Ar having At.wt. 39.9 a.m.u. was placed before K having At. Wt. 39.1 a.m.u.

v)The properties like valency ,reactivity ,electro negativity, can not be explained in the terms of periods and groups .

 Modern periodic table :The periodic table in which elements are arranged in the table with the increasing order of their atomic number is called Modern  periodic table .It is also called long form periodic table .It was formed by Henry Moseley.

Modern periodic law: It states that the physical and chemical properties of elements are periodic functions of their atomic number .

Group: The elements arranged in vertical column of   periodic table is called groups .There are 18 groups. Except zero group and vii the groups from i to vii are divided into sub group A and sub group B .

Period :The elements arranged in horizontal row with increasing order of atomic number are called periods. There are 7 periods and they are numbered as 1^st ,2^nd ,3^rd ,4^th  ,5^th ,6^th and 7^th  periods .

Characteristics of modern periodic table :

i)The elements are arranged on the basis of their increasing atomic  number in the modern periodic table .

ii) There are seven periods i.e. horizontal rows in modern periodic table .

Period	1st	2nd	3rd	4th	5th	6th	7th
N.of elements	2	8	8	18	18	32	26
Form  of Periods	Very short	Short	Short	Long	Long	Very long	Long But incomplete

 iii)In the modern periodic table there are 18 groups which are named by following two ways .

According to inter national pure applied chemistry (IUPAC)
1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18
According to modern periodic table
IA	IIA	IIIB	IVB	VB	ViB	VIIB	VIII	VIII	VIII	IB	IIB	IIIB	IVB	VB	VIB	VIIB	0

 iv)The elements between group 3 and group 12 are placed between reactive metal and non metal .These elements are called transition metal .These element are also called d-block elements or these elements have variable valency .

v)There are separate place for Lanthanides and Actinides at the bottom of modern periodic table .These elements are also called f-block of elements .

                                       Differences between Mendeleev’s and Modern periodic table

Classification of elements in modern periodic table :

In modern periodic table the elements are classified following ways :

Metal :The elements which have 1 to 3 electrons to their valence shell are called metals .They can conduct heat and electricity and also can develop electropositive charge by losing electrons .

For example :

i)Alkali metal :The elements of IA group in modern periodic table are called alkali metal , because they are dissolve in water to form metal hydroxide or alkali .

These metals are called very reactive metals because they have only one electrons to their valence so loss one electron very quickly to complete their valence shell .They are also called lightest metal .For example  :Na (Sodium), K (potassium ) etc.

ii)Earth alkaline metals :The elements of IIA group in modern periodic table are called earth alkaline metals, because they are found in the form of oxide on the surface of earth and react with water to produce alkali .For example : Mg (magnesium ) Ca (calcium ).

Transition elements : The elements of groups from IB to VIIB and VIII are called transition elements. They have variable valency. These elements are also called d-block of elements  .

Non metal : The elements which have 4 to 8 electrons to their valence shell are called Non metals .They are bad conductor  heat and electricity and also can develop electronegative charge by gaining electrons . For example :

i)Chalcogens :The elements of VIA group in modern periodic table are called chalcogens ,because these elements are found combined with copper in nature .For example :O (oxygen), S (Sulphur )  etc .

ii)Halogens: The elements of VIIA group in modern periodic table is called  halogen ,because they react with hydrogen to from acid from which simple salt also can be produced I.e. halogen =salt producer .

This group of elements  are also called very reactive non metal because they have 7 electrons to their valence so they receive 1 electron very to complete their valence .

For example : F (Fluorine) ,Cl (chlorine ) etc.

iii)Noble gas or inert gas :The elements of 0 group in modern periodic table are called Noble gas .because they have already 8 electrons to their valence shell so they neither receive nor donate electrons to complete their valence shell .For example :He (Helium), Ne (Neon) ,Ar (Argon ) etc.

Metalloid :The elements which are the poor conductor of heat and electricity are called metalloids or semi conductors  .These elements having both the properties of both metals and non metals .For example :Born (B), Silicon (Si), Arsenic (As) etc.

2n² rule :The rule that gives the maximum number of electrons present in the shell is called 2n²   rule .For example :

i)K- shell = 2n²  

               = 2 x1²  =2 electrons.

ii)L- shell  = 2n²

           =2x 2²    = 8 electrons

iii)  M  -Shell =  2n²

                       = 2x 3²  =18 electrons

Name of shell                                  Number of shell

K  =                                          1

L  =                                          2

M  =                                         3

N=                                           4

O  =                                         5

P  =                                          6

Q   =                                        7

Differences between shell and sub shell .

Shell	Sub shell
i)A circular path on which electrons revolute around the nucleus is called shell . ii) It is denoted by K,L,M,N,O,P,Q	i)A part of shell is known as sub shell .ii) It is denoted by s,p,d,f

Difference between orbit and orbital

Orbit	Orbital
i)A circular path on which electrons revolute around the nucleus is called shell . ii)All orbit are circular and disc like .	i)The region around  nucleus in which probability of finding the electrons  maximum is called orbital. ii)Different orbital have shape and half filled or full filled orbital more stable than other .

Valency : The  combine capacity of an elements with another elements is known as velency  .It is represented by  1,2,3,4,5,6 .

Valence shell :The outer shell of an atom of the elements is called valence shell .

Valence electrons : The electrons present in the outer most shell of an atom is called valence electrons .The number of valence electrons determine the valency of an atoms .

Atomic size or radius : The distance between the outermost shell and the centre of nucleus of that atom is called atomic size.

Chemical reactivity : The tendency of an elements to take part in chemical reaction is called chemical reactivity .It depends on following factors :

i)Valence electrons   

 ii)Atomic size or radius  

iii)Temperature   

iv)Catalyst

Ionization potential : The amount of energy required to remove a loosely bounded electrons from the shell of an atom .It is measured in electrons volt .It decreases on moving from top to bottom in a group and increase on moving from left to right in a periods .

iii)Electro-negativity :The tendency of an atom to attract electrons towards itself when combined in a compound is known as electro-negativity. It increases on moving left to right on moving in a period due to decreases of atomic size .Similarly the chemical reactivity of decreases from top to bottom in a group due increases of atomic size .

 Electronic configuration :The systematic  distribution of electrons according of their shell and sub shell is called electronic configuration.

Electronic configuration formula :

Note :

Metal =Valence electrons :1,2,3 For example :Na, K

Non Metal= Valence electros:5,6,7  for example :Cl,O, Br

Metalloid = valence electrons :4 ,For example:Si, Ge, As, Te

Inert gas: valence electrons: 8 For example:Ne ,Ar, Kr ,xe, Ra

N. of group : Total valence electrons i.e.  IA ,IIA ,IIIA group

N. of  period =: N. of shell

Valency :valence electron 1=1 ,2 =2,3=3,4=4,5=3,6=2,7=1,and 8=0 valency

For example :A element have 1 electron and B element have  electrons to their valence so A elements can loss easily 1 electrons than that of 2 electrons of B elements therefore A element is more reactive than that of B elements .

For example : A element have 7 electrons and B element have 6 electrons to their valence shell ,so A element easily gain 1 electrons than that of 2 electrons of B elements to complete their valency shell, therefore A element is more reactive than that of B elements .

For example : The atomic size of B element is larger than that of A element ,due larger atomic size of  B element the nuclear attraction to the valence shell is less than that of A element ,so B element can more easily loss 1 electron than that of 1 electron of A element , therefore B element is more reactive than that of A element .

For example : The atomic size of A element is smaller than that of B element ,due smaller atomic size of  A element the nuclear attraction to the valence shell is more than that of B element ,so A  element can more easily gain 1 electron than that of 1 electron of B element , therefore B element is more reactive than that of A element .

Chemical reactivity in period :The chemical reactivity of metal decreases gradually while moving from group 1 to 14 group or left to right side of a period ,similarly chemical reactivity of non- metal increases gradually while moving 15 to 17 group or left to right  in period due to increase of number of valence electron .

Chemical reactivity of metal  ∝  1/Reactivity

Chemical reactivity non metal  ∝ valence electrons

Chemical reactivity in group :The chemical reactivity of metal increases gradually while moving from top to bottom in 1 to 14 group ,similarly the chemical reactivity of non metals decreases gradually while moving from top to bottom in 15 to 17 group due to increase of size of atom .

Chemical reactivity of metal   ∝ atomic size

Chemical reactivity non metal ∝ 1/  size of atom

Block of modern periodic table :On the basis of electronic configuration in sub shell the elements in modern periodic table are divided into 4 blocks :

i)S-block of elements :The elements of modern periodic table having last electron in s-sub shell are called s-block of elements .For example : IA and IIA group of elements .

ii)P-block of elements : The elements of modern periodic table having last electron in P-sub shell are called P-block of elements .For example :IIIA,IVA,VA,VIA,VIIA, and 0  group of elements .

iii)d- block of elements : : The elements of modern periodic table having last electron in d-sub shell are called d-block of elements .For example :IB to VIIB and VIII group of elements .

f-block of elements : : The elements of modern periodic table having last electron in f-sub shell are called f-block of elements .This block is situated at the bottom of modern periodic table .For example :

Lanthanides series :Elements with the atomic n. from 58 to 71 after lanthanum(La) are called Lanthanides series .They are  14 in number also called rarer metal .

Actinides series :Elements with the atomic n. from 90 to 103 after Actinium(Ac) are called Actinides series .They are 14 in number also called artificial radio-active metals. 

1.)Atomic number of Na is 11 and oxygen is 8 respectively .Answer the following questions on the basis of that .

i)Write the electronic of Na, and  O .

ii)Write name the group of Na and O .

iii) Write name the period of Na,and O .

iv)Write valency of Na and O and why ?

v)Which one is metal and Non metal .

vi)Which one is more reactive between Na and O ?

i)Na =11

1s² ,2s² ,2p^6, 3s¹

 K          L       M

ii) O=9

1s², 2s², 2p⁴

K          L

ii)Na =IA group

   O=  VIA group

iii)Na =3^rd period

     O =2^nd period

iv) Na =1 valency because it have 1 electron to their valence shell to can easily loss 1 electron to complete their valence shell .

     O =   2 valency because  it have 6 electrons to their valence shell to can easily gain 2 electrons to complete their valence shell .

v)Na =metal

 O = Non metal

vi)Sodium(Na) have 1 and Oxygen(O) have 6 electrons to their valence shell so sodium can easily loss  1 electrons than that of gain 2 electrons of Oxygen, therefore Na is more reactive than that of O .

             Unit.:- 8    Chemical reaction

 

The combine capacity of element or radical to another element or radial to form compound is called  valency .

Or  the capacity of element to sharing or losing of valence electrons to their valence shell is called valency . It is represented by the numbers i.e. 1,2,3,4,5,6, For example valency of Oxygen is 2 ,hydrogen is 1

Radical :A radical is an atom or group of atoms different element having positive or negative charge and act as single unit during chemical reaction is called radical .They are two types :

i)Electropositive radical or Basic radical :The radical which have the capacity of losing electrons and carry positive charge are called electropositive radical .For example Mg⁺⁺ ,(NH₄)

Radical            Valency of elements              Valency of radicals

Ammonium  (NH₄)   = + 5-4                =      +1

 ii)Electronegative radical or acidic radical :The radical which have the capacity of gaining electrons and carry negative charge are called electronegative radical .For example :O^{-- --}  (SO₄)

Radical            Valency of elements              Valency of radicals

Carbonate (CO₃)  = +4-6                    = -2

Bicarbonate (HCO₃)  = +1+4 -6                   = -1

Sulphate (SO₄)     = +6-8                    =2

Bisulphate (HSO₄)  =+1+6 -8                       =  -1

Nitrate (NO₃)  = +5-6                                     = -1

Hydroxide (OH) = -2+1                                   = -1

Valency chart :

S.N.	Name of element s	Symbol		Valency
		Electro positive	Electro Negative
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21	Hydrogen  or hydride Potassium Sodium Silver Gold-I(Aurous) Copper –I (Coprous) Mercury –I(Mercurous) Ammonium Bicarbonate Bisulphate Hydroxide Nitrate Nitrite Chlorate Chlorite Chlorine or chloride Bromine or bromide Fluorine  or fluoride Iodine or iodide Cyanide Bisulphite	H K Na Ag Au Cu Hg (NH4)	(HCO3) (HSO4) (OH) (NO3) (NO2) (ClO3) (ClO2) Cl Br Fl I CN (HSO3)	1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43	Barium Calcium Magnesium Nickel Zinc Coppper –II(Cupric) Iron –II(Ferrous) Mercury –II(Mercuric) Lead –II (Plumbous) Tin-II(Stannous) Magnanese Iron –II(Ferrous) Oxygen or oxide  Sulpher or Sulphide Peroxide Carbonate Sulphate Sulphite Chromate Dichromate Silicate Stanate 11	Ba Ca Mg Ni Zn Cu Fe Hg Pb Sn Mn Fe	O S O2 (CO3) (SO4) (SO3) (CrO3) (Cr2O7) (SiO3) (SnO3)	2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2
44 45 46 47 48 49 50	Aluminium Nitrogen or Nitride Phosphrous  or phosphide Chromium Iron-III (Ferric) Gold –III (Auric) Phosphate	Al     Cr Fe Au	N P       (PO4)	3 3 3 3 3 3 3
51 52 53 54 55	Lead –IV (Plumbic) Tin-IV(Stanic) Sulpher or sulphide Silicon Carbon or carbide	Pb Sn S Si C		4 4 4 4 4
56 56	Nitrogen or nitride Phosphrous	N P		5 5
57	Sulpher	S		6

Molecular formula :The symbolic representation of molecules of substance which show actual number of atoms present in the molecules is called molecular formula or chemical formula .For example :i) Magnesium chloride =MgCl₂, Sodium sulphate =Na₂(SO₄ ) etc.

Ways of writing molecular formula : This method is called criss –cross method.

i)Write the symbols side by side but electropositive is written first and then electronegative .

ii)Write the valency of each atom at top of its symbol .

iii)Divide the valency numbers by highest common factor then inter change the valency of symbol .

iv)Write the  inter changed valency number to the lower of the symbol .

For example:

Molecular formula of some compounds :

Name of compounds           Molecular formula

Water =                      H₂O

Carbondixide             =            CO₂

Carbonmonoxide =    CO

Ammonia          =        NH₃

Castic soda                 =    Na(OH)

Castic Potash                         = K(OH)

Methene                     = CH₄

Calcium carbonate  or limestone     =Ca(CO₃)

Lime water                 = Ca(OH)₂

Lime                            ₌ CaO

Hydrochloric acid      =HCl

Sulphuric acid                        H₂(SO₄)

Nitric acid                   =H(NO₃)

Carbonic acid                         =H₂(CO₃)

Acetic acid                  =CH₃COOH

Carbon sulphide        =CS₂

Nitric oxide                =NO

Hydrogen peroxide   =H₂O₂

Iron oxide (rust)                     =Fe₂O₃

Manganese dioxide   =MnO₂

Silica(Silicon oxide ) =SiO₂

Urea                            =NH₂-CO-NH₂

Diatomic elements    =H_2,O_2,N_2,Cl_2,Br_2,I_2,F_2,

Chemical reaction :-The exchange ,combustion or decomposition that occurs in the molecules of substances during a chemical change is called chemical reaction .

Chemical equation : The symbolic representation of the chemical reaction by writing the symbol and formula is called chemical equation .It is divided into two parts :

i)Reactant :The substance which takes part in chemical are called reactants .They are always  written in the left side of the chemical equation .

ii)Product :The substance obtained from a chemical reaction are called product .They are always written in the right side of the chemical equation .

i)Hydrogen +Oxygen                  Water

2H₂    +O_2→                 2 H₂O

ii)Sodium +Oxygen                  Sodium oxide

Na +O_{2      →}                               Na₂O

Word equation :The chemical equation in which the names of substance and products are expressed in the form of word is called word equation . For example :

 i)  Hydrogen + Oxygen    _→                                     water

ii) Magnessium + Oxygen   _→                                  Magnesium oxide

iii)Calcium carbonate                    _→                         Calcium oxide +Carbon dioxide

Types of chemical reactions :There are 4 types chemical reaction:

1)Combination reaction :The chemical reaction in which two or more elements or compounds combine to form a single compound is called combination reaction .For example :

1)Sodium + Oxygen                 Sodium oxide

4Na     `+ O_{2        →}                      2Na₂O

2)Magnesium + Oxygen       _→                            Magnesium oxide

2Mg     +          O_{2       →}                           2MgO

3)Hydrogen + Chlorine      _→                   Hydrogen chloride

H₂   +  Cl_{2                                →                                    2} HCl

4)Zinc +Chloride      _→                 Zinc Chloride

Zn  + Cl_2   →                     ZnCl₂

5)Nitrogen + Hydrogen       _→                          Ammonia

N₂      +     2H_{3                     →}       2NH₃

6)Iron + Oxygen        _→                Iron oxide

Fe   +  O_{2                              →}               Fe₂O₃

7)Magnesium +Nitrogen               _→                   Magnesium Nitride

3Mg +  N_{2                        →}          Mg₃N₂

8)Carbon dioxide +Water        _→                         Carbonic acid

  CO₂        +H₂O                 _→              H₂CO₃

9)Aluminum + Oxygen         _→                 Aluminum oxide

Al  +O_{2                            →}           Al₂O₃

10)Aluminum + Chlorine                       _→      Aluminum Chloride

2Al    + 3Cl_{2              →}                           2AlCl₃

11)Ammonia +Hydrochloric acid    _→      Ammonium chloride

NH₃       + HCl        _→                    (NH₄)Cl

12)Nitrogen +  Oxygen          _→               Nitric oxide

N₂     + O_{2              →}          2NO

13)Calcium oxide + Water    _→                Calcium hydroxide

CaO     +  H₂O           _→             Ca(OH)₂

14)Sodium oxide        +Water       _→                  Sodium hydroxide

Na₂O   +H₂O       _→                       2Na(OH)

15)Magnesium oxide +Water                _→           Magnesium hydroxide

16)Ammonium oxide +Water  _→           Ammonium hydroxide

(NH₄)₂O    + H₂O       _→                2(NH₄)(OH)

2.)Decomposition  reaction :-The chemical reaction in which a compound split or decompose into two or more elements or compound is called decomposition reaction .For example:

1)Water        _→                             Hydrogen   + Oxygen

2H₂O             _→                 2H₂     + O₂ 

2)Potassium chlorate    _→       Potassium chloride + Oxygen

2K(ClO₃)    _→                    2KCl     + 3O₂

3)Calcium carbonate     _→     Calcium oxide +Carbon dioxide

Ca(CO₃)            _→                         CaO                 + CO₂

4)Magnesium oxide       _→           Magnesium +Oxygen

2Mg O       _→                    Mg + O₂

5)Hydrogen peroxide   _→                Water + Oxygen

2H₂O_{2                                  →}                     2H₂O +O₂

6)Calcium bicarbonate          _→               Calcium carbonate +Carbon dioxide +Water

Ca(HCO₃)_{2           →}          Ca(CO₃) +CO₂    +H₂O

7)Magnesium bicarbonate     _→              Magnesium carbonate +Carbon dioxide +Water

Mg(HCO₃)_{2         →}                       Mg(CO₃) +CO₂  +H₂O

8)Silver Bromide     _→                  Silver  + Bromine

2Ag Br       _→                                2Ag  +Br₂

 

9)Potassium Permanganate  _→      Potassium manganate  +Manganese dioxide +Oxygen

2KMnO_{4     →}                   K₂MnO₄ +MnO₂  +O₂

10)Ammonium carbonate            _→      Ammonia +Carbon dioxide +Water

(NH₄)₂(CO₃)  _→                2NH₃    +CO₂    +H₂O

 3.Displacement reaction :The chemical reaction in which an element or radical of a compound is displaced by another element or radical of compound is called displacement reaction .For example :

1)Zinc +Sulphuric acid  _→                 Zinc sulphate +Hydrogen

Zn +  H₂(SO₄)          _→          Zn(SO₄ )  +   H₂

2)Zinc  + Hydrochloric acid            _→     Zinc chloride + Hydrogen

  Zn       +   2HCl              _→          ZnCl₂   +  H₂

3)Potassium + Nitric acid            _→ Potassium Nitrate +  Hydrogen

   2 K  + 2H(NO₃)      _→                 2K(NO₃)    +  H₂

3)Iron + Copper Sulphate           _→    Iron Sulphate +Copper

2 Fe +3 Cu(SO₄)     _→             Fe₂(SO₄)₃   + 3Cu

4)Aluminum  + Hydrochloric acid  _→           Aluminum chloride +Hydrogen

2 Al      +6 HCl                  _→                       2AlCl₃  + 3 H₂

5)Magnesium + Copper Sulphate _→          Magnesium Sulphate + Copper

 Mg + CuSO_{4                     →}                    Mg(SO₄)  + Cu

6)Sodium + Water     _→                Sodium hydroxide + Hydrogen

2 Na +2H₂O          _→                     2Na(OH) +H₂

7)Magnesium bicarbonate        _→                        Magnesium carbonate +Carbon dioxide +Water

Mg(HCO₃)_{2                     →}                        Mg(CO₃) +CO₂  +H₂O

8)Silver Bromide       _→                             Silver  + Bromine

2Ag Br                             _→                       2Ag  +Br₂

 

9)Potassium Permanganate    _→                Potassium manganate  +Manganese dioxide +Oxygen

2KMnO_{4           →}                          K₂MnO₄ +MnO₂  +O₂

10)Ammonium carbonate        Ammonia +Carbon dioxide +Water

(NH₄)₂(CO₃)         _→                       2NH₃    +CO₂    +H₂O

 3.Displacement reaction :The chemical reaction in which an element or radical of a compound is displaced by another element or radical of compound is called displacement reaction .For example :

1)Zinc +Sulphuric acid       _→                        Zinc sulphate +Hydrogen

Zn +  H₂(SO₄)                _→                 Zn(SO₄ )  +   H₂

2)Zinc  + Hydrochloric acid                 _→             Zinc chloride + Hydrogen

  Zn       +   2HCl           _→                          ZnCl₂   +  H₂

3)Potassium + Nitric acid           _→              Potassium Nitrate +  Hydrogen

   2 K  + 2H(NO₃)                     2K(NO₃)    +  H₂

3)Iron + Copper Sulphate             _→               Iron Sulphate +Copper

2 Fe +3 Cu(SO₄)      _→                         Fe₂(SO₄)₃   + 3Cu

4)Aluminum  + Hydrochloric acid             _→             Aluminum chloride +Hydrogen

2 Al      +6 HCl           _→                                           2AlCl₃  + 3 H₂

5)Magnesium + Copper Sulphate    _→                     Magnesium Sulphate + Copper

 Mg + CuSO_{4                          →}                            Mg(SO₄)  + Cu

6)Sodium + Water       _→                           Sodium hydroxide + Hydrogen

2 Na +2H₂O          _→                                  2Na(OH) +H₂

 

7)Magnesium+ Water     _→                      Magnesium hydroxide +Hydrogen

 Mg + H₂O      _→                            Mg(OH)₂          +H₂

8)Zinc +Silver Nitrate  _→                          Zinc Nitrate +Silver

   Zn + 2Ag(NO₃)        _→                            Zn(NO₃)₂  +2Ag

9)Calcium +Water       _→                          Calcium hydroxide +Hydrogen

  Ca +2H₂O      _→                           Ca(OH)₂ +H₂

10)Aluminum +Sulphuric acid       _→                                Aluminum Sulphate+ Hydrogen

2Al+3 H₂(SO₄)      _→                                  Al₂(SO₄)₃ +6H₂

11)Copper +Silver Nitrate    _→                     Copper Nitrate +Silver

   Cu +  2Ag(NO₃)           _→                        Cu(NO₃)₂ +2 Ag

12)Ammonia +Chlorine           _→             Ammonium Chloride +Nitrogen

8NH₃ +3Cl_{2            →}             6 ( NH₄)Cl     +N₂    

13)Calcium Chloride +Silver Nitrate      _→                    Calcium Nitrate +Silver Chloride

CaCl₂ + 2Ag(NO₃)        _→                           Ca(NO₃)₂+2AgCl

14)Calcium Carbonate +Hydrochloric acid      _→                         Calcium Chloride +Carbon dioxide +water

 Ca(CO₃) +2HCl     _→                     CaCl₂ +CO₂ +H₂O

15)Sodium Chloride +Silver Nitrate         _→                      Sodium Nitrate+ Silver Chloride

 NaCl +Ag(NO₃)    _→                     Na(NO₃)+ AgCl

16)Calcium Carbonate +Sulphuric acid            _→             Calcium Sulphate +Carbon dioxide +Water

Ca(CO₃)+H₂(SO₄)       _→                             Ca(SO₄)+CO₂ +H₂O

17)Magnesium Sulphate +Sodium Carbonate     _→                                            

Magnesium Carbonate +Sodium Sulphate

Mg(SO₄)+Na₂(CO₃)        _→                        Ma(CO₃)+Na₂(SO₄)

4)Acid –Base reaction :The Chemical reaction in which an acid react with a base to form salt and water is called acid- base reaction .In acid base reaction both acid and base loss their properties during chemical reaction and form neutral substance salt and water ,so it is also called Neutralization reaction .

Some acids :

i)Hydrochloric acid=HCl

ii)Sulphuric acid =H₂(SO₄)

iii)Nitric acid =H(NO₃)

iv)Carbonic acid =H₂(CO₃)

Some bases :

i)Metal oxide ePdf = Mgo,Na₂O,K₂O,CaO etc.

ii)Metal hydroxide ePdf = Na(OH),K(OH),Ca(OH)₂ etc.

1)Sodium Hydroxide +Hydrochloric acid    _→                   Sodium Chloride + Water

2Na(OH)+2HCl        _→                               2NaCl +H₂O

2)Sodium Oxide +Hydrochloric acid    _→                       Sodium Chloride +Water

Na₂O   +2HCl          _→                   2NaCl +H₂O

3)Calcium Oxide +Sulphuric acid  _→                      Calcium Sulphate +Water

CaO +H₂(SO₄)   _→                           Ca(SO₄)+H₂O

4)Magnesium Oxide +Hydrochloric acid   _→                        Magnesium Chloride +Water

MgO+2HCl         _→                        MgCl₂ +H₂O

5)Potassium Hydroxide + Hydrochloric acid       _→                      Potassium Chloride +Water

2K(OH)+2 HCl                 _→                       2KCl +H₂O

6)Sodium Hydroxide +Sulphuric acid     _→                        Sodium Sulphate +Water

2Na(OH) +H₂(SO₄)  _→                         Na₂(SO₄)+2H₂O

7)Ammonium Hydroxide +Sulphuric acid      _→                            Ammonium Sulphate + Water

2(NH₄)(OH) +H₂(SO₄)      _→                          (NH₄)₂(SO₄)+H₂O

8)Magnesium Hydroxide + Nitric acid         _→                             Magnesium Nitrate + Water

Mg(OH)₂ +2H(NO₃)       _→                         Mg(NO₃)₂   +H₂O

Types of reaction according to heat :There are two types of reaction according to heat :

1.)Exothermic reaction : The reaction in which heat is released to the surrounding  is called exothermic reaction. For example :

i )C + O _{2                      →}                                 CO₂  +Heat

ii) C₆H₁₂O₆ +6O_{2            →}           6CO₂ + 6H₂O Energy +Heat

2.)Endothermic reaction :The reaction in which heat is absorbed from the surrounding is called endothermic reaction .For example :

i)Ca(CO₃)  + Heat                   _→               CaO +CO₂

ii)2K(ClO₃)            _→                   2KCl + 3O₂

Some rules of what happens :

Reactants                                                       Product

i)Single 2 elements   =    Combination of element .i.e.

Na + Cl_{2          →}                                     NaCl

Mg + O_{2                  →}                                                               MgO

ii)Metal  +Water =      Metal Hydroxide i.e.

Na+ H₂O       _→                           Na(OH)

Ca  +H₂O      _→                           Ca(OH)₂

iii)Metal +Water  = Metal Hydroxide +Hydrogen i.e.

 Mg + 2H₂O       _→                    Mg(OH)₂ +H₂

Na+2 H₂O    _→                      Na(OH)₂  +H₂

iv)Acid+ Base  = Salt + Water

  HCl +Na(OH)     _→                      NaCl +H₂O

H₂(SO₄) +Na₂ O     _→                    Na₂(SO₄) +H₂O

v)Carbonate + acid =  Carbon dioxide + Water  i.e.

 Ca(CO₃)+2HCl     = CaCl₂  + CO₂  +H₂O

Balanced chemical equation : The chemical equation written by balancing the N. of atoms of element on both sides of reactants and products is called balanced chemical equation .For example :

2H₂ + O_{2      →}                            2H₂O

Advantages  or information can be obtained from of balanced chemical reaction : Following information can be obtained from balanced chemical equation :

i)The types of chemical equation

ii)Names of reactants and produced

iii)Molecular formula  or symbols of reactants and products

iv)N. of atoms and molecules of reactants and products .

Limitation of a balanced chemical equation :The information which can not show a balanced chemical equation are called limitation of balanced chemical equation .They are as following :

i)Rate of chemical equation .

ii)Concentration of reactants .

iii)Duration of chemical reaction .

iv)Conditions necessary for chemical reaction .

Factors affecting chemical reaction or chemical change :

1)Heat :When reactants are heated more kinetic energy provides to the reactants molecules ,that increase the rate of reaction by colliding with one another molecules .i.e.

Calcium Carbonate        _→                     Calcium oxide +Carbon dioxide                    

   Ca(CO₃)         _→                         CaO + CO₂

2)Light :Light makes the reactants molecules more reactive and help to increase the rate of reaction .

Silver Bromide    _→            ^Light                 Silver +Bromide

2AgBr     _→               ^Light                2Ag + Br₂

3)Electricity :The electrical energy help the ions to move to wards  opposite. charged electrodes that brings out a chemical change and increase the rate of reaction .

Water      _→                    Hydrogen +Oxygen

2H₂O    _→               ^Electrolysis                    2H₂ +   O₂

4)Direct Contact :Some  active substance react on coming in direct contact with other .i.e.

Sodium + Chlorine   _→               ^{Direct contact}                  Sodium Chloride

2Na + Cl_2  →             ^{Direct contact}     2 NaCl

5)Pressure :Some chemical reaction takes place by the application of pressure .i.e.

Nitrogen + Hydrogen     ^{200 atm-900 atm}                Ammonia

N₂  +3H_2  →             ^{200 atm-900 atm}                 2 NH₃

6.)Surface area :The rate of chemical reaction is directly proportional to the surface area of the reacting molecules ,because there is more chances to contact and collision between reacting particles .For example :During preparation of hydrogen gas if the granulated zinc has more area the chemical reaction proceeds in faster rate .

7.)Solution :The chemical reaction between some compounds only occurs when they are in the state of solution .For example :Silver nitrate and Sodium chloride only react when they are mixed in the solution state

Ag(NO₃) (aq.) + NaCl (aq.)       _→                       Na(NO₃) +AgCl

8.)Concentration : The rate of chemical reaction increase with the increase in the concentration of the reactants because concentration of reactants increase the number of molecules per unit volume that increases more collision between reactants molecules .

9)Catalyst :A chemical substance which changes the speed of rate of chemical reaction with out changing itself is called the catalyst . There are 2 types of catalyst :

i)Positive catalyst :A catalyst which increase the rate of chemical reaction is called positive catalyst .i.e. Manganese dioxide acts as positive catalyst in a decomposition reaction of potassium chlorate .

Potassium Chlorate     _→             MnO₂            Potassium Chloride + Oxygen 

2K(ClO₃)    _→            MnO₂        2KCl +3O₂

ii)Negative Catalyst :A catalyst which decrease the rate of chemical reaction is called negative catalyst .i.e. Glycerin acts as negative catalyst in decomposition of hydrogen peroxide .

2H₂O_2  →          Glycerin      2H₂O  + O₂

Gram atomic weight : The atomic weight of an element expressed in gram is known as gram atomic weight of that element .For example :The gram atomic weight of oxygen is 16 gm ,because the atomic weight of oxygen is 16 .

1.)Find the atomic weight of Na, K ,and Ca atoms .

            Na =11+12

                 =23 gm

           K = 19+20

               =  39 gm

          Ca =20+20

               = 40 gm

Gram molecular weight :The molecular weight of the substance is expressed in gm is known as gram molecular weight of that substance .For example :The gram molecular weight of water is (H₂O) is 18 gm because molecular wt of water is 18 .

1.)Find the molecular weight of given compounds .

i)H₂O

= 1x2+16

18 gm

ii)CaO

= 40+16

=56 gm

iii)Ca(CO₃)

= 40+12+16x3

=40+12+48

=100gm

1mol: The gm atomic wt. or gram molecular of any substance is known as 1 mol of that substance .

1 mol of any substance =Gm atomic weight or Gm molecular wt of that substance .

i)Calculate the mass of 8 mol of water .

Gram molecular weight of water =H₂O

                                                            =1x2+16

                                                            =18 gm.

Mass of 1 mol of water =Gram molecular wt. of water

                                            = 18gm .

Therefore ,mass of 8 mol of water =18x8

                                                                 =144gm.

ii)Convert 5 gm of Ca  into mol .

Gram at. wt. of Ca =1 mol of Ca

40 gm of Ca = 1mol of Ca

1gm of Ca  =1/40

؞5 gm of Ca =1/40   x 5

  Therefore 5 gm of Ca = =0.25 mol of Ca .

         

     

          Unit :-9 Acid Base and Salt

Acid : A substance which gives hydrogen ions (H⁺) when dissolved in water is called acid. For example :

HCl =hydrochloric acid

H₂(SO₄)= Sulphuric acid

H(NO₃)= Nitric acid

H₂(CO₃)=Carbonic acid

i)HCl   →              H⁺   +   Cl^-

Types of acid :

A)On the basis of origin :They are 2 types :

1)Organic acid :The acid which are obtained from living being( i.e. plants and animals  )are called organic acid .They have carbon atoms .For example :Carbonic acid =H₂(CO₃), Acetic acid =CH₃COOH, Citric acid = C₆H₈O₇ etc.

2.)Inorganic acid :The acid which are obtained from minerals are called inorganic acid .They do not have carbon atoms .For example : HCl = Hydrochloric acid

H₂(SO₄) = Sulphuric acid

H(NO₃)=Nitric acid

B) On the basis of strength of acid :They are 2 types :

1)Strong acid :The acid which undergoes complete dissociation in aqueous solution and producing high concentration of  H⁺ ions are called strong acid .It show low p^H value and good conductor of electricity .For example :H₂(SO₄) =Sulphuric acid

HCl =Hydrochloric acid

H(NO₃) =Nitric acid

2.)Weak acid :The acid which undergoes partial dissociation in aqueous solution and producing low concentration of H⁺ ions is called weak acid .They have high P^H value and poor conductor of electricity. For example :H₂(CO₃)=Carbonic acid, Acetic acid =CH₃COOH etc.

Properties

Physical properties

i)It possess sour test .

ii)Strong acid are highly corrosive in nature so,they are not tested i.e. H₂(SO₄), HCl etc.

iii)Some acid are poisonous i.e. Hydrogen cyanide =HCN is most poisonous acid .

iv)Some acid are solid i.e. Citric acid =C₆H₈O₇ and some are liquid i.e. Hydrochloric acid =HCl .

v)Acid change blue litmus paper into red ,methyl orange into pink, phenolphthalein  into colourless ,and red cabbage juice into red colour .

Chemical properties

i)When acid react with base gives salt and water .For example

HCl  +  Na(OH)   →                    NaCl  + H₂O

 Acid    Base                          Salt       water

ii)When acid react with reactive metal i.e. Na,K, gives salt and hydrogen gas .

2Na    + 2HCl   →                       2NaCl `+ H₂

^{Metal      Acid                              salt}       

iii) When acid react with metallic carbonate or bicarbonate gives salt water and carbon dioxide.

Na₂(CO₃)    + 2HCl                →   2NaCl   +CO₂  +H₂O

                      ^{acid                            salt}                      

Na(HCO₃) +HCl   →                   NaCl + CO₂   +H₂O

                    _acid

 Uses of acid

i)Sulphuric acid is used in the manufacture of fertilizer i.e. ammonium sulphate ,paint, and storage battery .

ii)Hydrochloric acid is used for cleaning of metal items .

iii)Nitric acid is used in the manufacturing of fertilizer i.e. ammonium nitrate ,plastic etc.

iii)Carbonic acid used for making soft drinks i.e. soda water .

iv)Tartaric acid is used for making baking powder .

v)Boric acid is used as antiseptic medicine .

Base :Metalic oxides or hydroxides which  are neutralized by acid to produce salt and water is called base .i.e. Na₂O,MgO,K₂O,CaO ,Ca(OH)_2, K(OH) etc. The bases which are water soluble are called alkali ,therefore all alkali are bases but all bases are not alkali because all bases are not water soluble .

Types of bases :On the basis of strength they are two type :

1.)Strong base :The bases which undergoes complete dissociation and produce high concentration of hydroxyl (OH)^-  ions are called strong base .It have high  P^H value. For example :K(OH)=Potassium hydroxide, Na(OH)=Sodium hydroxide etc.

2.)Weak base :The bases which undergoes partially dissociation and produce low concentration of hydroxyl (OH)^- ions are called weak base. It have low P^H value .For example :(NH₄)(OH) =Ammonium hydroxide ,Mg(OH)₂₌Magnesium hydroxide etc.

Properties

Physical properties

i)Bases are bitter in test and soapy in touch .

ii)Bases have P^H value more than 7.

iii)They change red litmus paper into blue ,methyl orange into yellow, phenolphthalein into pink and red cabbage juice into green colour.

Chemical properties

i)When base react with acid gives salt and water .

Na(OH)  +HCl   →                                 NaCl   +H₂O

 ^{base             acid                                       salt}

ii)When alkali solution react with ammonium chloride ,salt ammonia and  water are obtained .

Na(OH) + (NH₄)Cl                →               NaCl   +NH₃        +H₂O

Alkali                                                       salt      ammonia

Uses of  bases

i)Na(OH) is used to make soap and paper .

ii)Ca(OH)₂  is used  to make cement ,white washing bulding and plaster .

iii)Mg(OH)₂ and Al(OH)₃ are used for making reducing hyperacidity .

iv)(NH₄)(OH) is used for making chemical fertilizer 

Salt: A  neutral substance which is formed as result of the reaction between acid and base is called salt .

Na(OH)  +HCl  →                                   NaCl  +H₂O  

  Base       acid                                         salt

Methods of preparation of salt

1.)By direct contact of element .For example :

2Na + Cl₂ →                                      2NaCl

                                                     Salt

2.)By reaction of metal with acid :For example :

2Na       +   2HCl                    →      2NaCl  +H₂

 Metal     acid                                   salt

 3.)By reaction of acid with base .For example .

HCl      +  Na(OH)  →                             NaCl  +H₂O

Acid        base                                           salt 

Types of salt :On the basis of chemical nature and method of formation :They are 3 types

1.)Neutral salt :The salt which is formed by the reaction between strong acid and strong base are called neutral salt .For example :

Na(OH)    + HCl  →                                      NaCl     +  H₂O

^{strong base  st. acid                         neutral salt}

2.)Acidic salt :The which is formed by the reaction between strong acid and weak base is called acidic salt .For example :

HCl   +  (NH₄)(OH) →                           (NH₄)Cl          +H₂O  

^{St. acid   weak base                                  Acidic salt}

3.)Basic salt :The salt which is formed by the reaction between strong base and weak acid is called basic salt .For example :

Na(OH) + H₂(CO₃) →                           Na₂(CO₃) +H₂O

^{St. base         weak  acid                              basic salt}

Properties of salt

i)Salt are salty in taste but some salt are bitter or test less .

ii)Salt are generally neutral but some salt are acidic or basic .iii)Most of salt are water soluble .

Uses of salt :

i)Common salt i.e. NaCl is used in daily life .

ii)Cu(SO₄) is used for plastering of fractured bone and making ceramics .

iii)Na₂(CO₃) is used for making detergent and softening hard water .

iv) Cu(SO₄) is used for electroplating ..

Indicator :-A chemical substance which can change  its colour when kept int acid  base and salt is called indicator .It is used to test the substances whether they are acid ,base or neutral .For example :

Universal indicator :A special types of indicator which is used  to measure the strength of acid and base, is called universal  indicator .It is prepared by mixing several organic indicator of different colour .It is found in the form of yellow litmus paper .

P^H Scale : A scale which is used to measure strength of acid and  base is called P^H  Scale ^.   Or A scale which shows the quantities of H⁺  present in acid and (OH)^-  ions present in base solution .The P^H  value of acid is inversely proportional to the strength of acid and directly proportional to the strength of base .In P^H scale the P^H value below 7 i.e. 1 to 6  represent acidity and above 7 i.e. 8 to 14 represent alkalinity where as 7 represent neutrality or salt .

P^H value of some common substances

1.Gastric juice (HCl)= 1to 3

2.Wine =3.5

3.Beer = 4.5 to 5.5

4.Milk =5.5

5.)Urine =5.5 to 7.5

6.)Blood =7.3 to 7.5

7)Washing soda =9

8.)Sodium hydroxide =14

9.)Salt = 7

10 .)Fertile soil. =7

Unit :-10     Gases (Carbon dioxide (CO₂), Ammonia (NH₃)

A) Carbondioxide =CO₂

1.Indtroduction :The molecular formula of carbon dioxide is CO_2,molecular weight is 44 a.m.u.  Air contains about 0.03% of carbon dioxide by volume .Its molecular structure is

2.Methods of general preparation of CO₂ :

1.)When carbon is burn in air with plenty of oxygen and carbon dioxide is obtained .

C +O₂                           →   CO₂

                                Carbon dioxide

ii.)When calcium carbonate is heated strongly and carbon dioxide is obtained .

Ca(CO₃)     →                     CaO     +  CO₂

Lime stone                             Lime

iii)When fuel like methane, ethane ,is burn in air carbon dioxide is obtained.

CH₄                +    2O₂           →     CO₂   +2 H₂O

Methane

3.)Method of lab. preparation CO₂  gas :

i.)Apparatus required :Wolf bottle ,Thistle funnel ,delivery tube, gas jar, beehive self, heating apparatus.

ii)Chemicals required:  Lime stone (marble), hydrochloric acid 

iii)Principle:- CO₂  gas  can be  prepared by treating pieces of calcium carbonate with  dil. Hydrochloric acid .

Reaction :

Ca(CO₃)      +   dil. HCl                  →   CaCl₂   +  CO₂  + H₂O

Lime stone

iv)Precaution: a)The apparatus should be made air tight .

b)The end of thistle funnel should be dipped into the acid in wolf bottle.

v)Test of CO₂ :a) When a burning match stick is placed near the mouth of gas jar containing CO₂ .If match stick extinguish the gas is CO2 gas ,because CO₂ gas is non supporter of combustion .

4.)Properties

1.)Physical properties :

i)It is colourless ,odourless and testless gas .

ii)It turns wet blue litmus paper into red .

iii)It is heavier than that of air .Therefore CO₂ gas can be collected down word displacement method of water  or it is collected by upward displacement of air .

iv)It dissolve in water so, it is not collected in water .

v)It is non supporter of combustion .

Chemical properties :

i)When carbon dioxide is treated with water carbonic acid is obtained .Therefore when blue litmus paper is introduced inside gas gar containing CO₂ it change in to red colour due to formation of carbonic acid.

CO₂  +    H₂O                    →      H₂(CO₃)

ii)When carbon dioxide is passed into lime water for long time in the beginning milky solution of insoluble calcium carbonate is obtained

If when carbon dioxide is passed continuously in the solution for long time the milky ness  disappear slowly due to the formation of water soluble calcium bicarbonate .

a)Ca(OH)₂    + CO₂               →     Ca(CO₃) +H₂O

Lime water                                 Milky sol_.

b)Ca(CO₃)  +H₂O              →    Ca(HCO₃)₂

iii)When burning magnesium ribbon is introduced into  gas jar filled with CO₂ ,white colour of MgO is produced along with the formation of black spots of  carbon .

2Mg  + CO₂                               →            2Mg O      + C                                   

                                                              Black

iv)When carbon dioxide react with water in presence of chlorophyll, and sun light ,Glucose and oxygen is obtained .

6CO₂    +   6H₂O                →    C₆H₁₂O₆    + 6O₂

                                                      Glucose

5.)Method of industrial preparation of CO₂  gas :

In industries carbon dioxide gas is prepared in large scale by heating lime stone at very high temp.  in the furnace .In this process lime is also produced .

Ca(CO₃)         ^Heat            →     CaO  +CO₂

Lime stone                               Lime

6.)Uses :

i)It is used by all green plant during photosynthesis .

ii)It is used as fire extinguisher .

iii)It is used for making dry ice to preserve meat, fruit etc. (A solid form of carbon dioxide which is obtained by cooling it about -78⁰C is called dry ice .)

Fire extinguisher :

Afire extinguisher is a metallic cylinder divided in to two section .The outer section is a metallic covering contains sodium bicarbonate =Na(HCO₃) and inner section is made up a glass vessel filled with conc. Sulphuric acid =H₂(SO₄)_.When  glass vessel is broken by pressing knob at the top of cylinder sulphuric acid gets mixed with sodium bicarbonate to form carbon dioxide . 

2Na(HCO₃) + H₂(SO₄)          →             Na₂(SO₄) +2H₂O+ 2CO₂

B.)Ammonia (NH₃)

1.)           Introduction :

La Voiser prepared first time ammonia gas .Its molecular formula is NH₃ ,molecular weight is 17 a.m.u. and its molecular structure is

Methods of general preparation of NH₃ gas :

i)When magnesium Nitrate is treated with water and ammonia gas is formed .

Mg₃N₂ +  6H₂O                         →         3Mg(OH)₂ +2NH₃

3.)Methods of lab preparation of ammonia gas :

i) i.)Apparatus required :Round bottom flask ,delivery tube, gas jar, , heating apparatus, lime tower

ii)Chemicals required:  Ammonium chloride ,Calciumhydroxide.

iii)Principle:- NH₃  gas  can be  prepared by treating mixture of Ammonium Chloride and of calcium hydroxide .

iv)Reaction :

2(NH₄)Cl  + Ca(OH)₂                       →                                   CaCl₂  + H₂O  + 2NH₃

                                                                                                                Ammonia

                                Fig.  Lab preparation of NH₃  gas .

v)Precaution :

i)The apparatus  should made air tight.

ii)The should be collected in gas jar by the downward displacement .

vi)Test of NH₃ gas :When a wet a red litmus paper is introduced in to gas jar containing ammonia gas . It change into blue colour due to formation of Ammonium hydroxide alkali .

4.)Method of industrial preparation of NH₃ gas : In industries  ammonia is prepared by Hyber’s process .In this process  ammonia gas is prepared by the direct combination of Nitrogen and Hydrogen gas under high pressure and high temperature in presence of  Fe catalyst .

N₂   +  3H₂   →        ^200atm/500C        2NH₃

                                                   Ammonia

5.)Properties :

Physical properties :

i)It is colourless ,testless , but strong pungent odour .

ii)It is highly soluble in water .

iii)It is lighter than that of air .

iv)It turns wet red  litmus paper  into blue colour due to formation ammonium hydroxide alkali.

Chemical properties .

i)When ammonia react with water an alkali ammonium hydroxide is formed .

NH₃   +  H₂O →                (NH₄)(OH)

                                             Alkali

ii) When ammonia react with acid ,salt are formed .

NH₃   +  HCl  →                 (NH₄)Cl

NH₃   +  H(NO₃)       →     NH₄(NO₃)

iii)When ammonia is treated with carbon dioxide at high temperature at 1500 ⁰C under certain pressure urea is formed .

2NH₃  +  CO₂        →                     NH₂ – CO – NH₂   + H₂O

                                                            urea

6.)Uses :

i)It is used for making chemical fertilizer .i.e. urea, ammonium sulphate .

ii)It is used for making  plastic, washing soda  etc.

iii)It is used for making medicine .

iv)It is used for develop blue print .

1.)Lime tower is used in lab preparation of ammonia gas ,why?

Ans. Lime tower help to form dry ammonia gas ,because when ammonia gas comes out from lime tower ,it absorb water of ammonia gas due to water soluble properties of ammonia .

2.)The mouth hard glass test tube is slightly slanted during the preparation of ammonia gas ,why ?

Ans. When mixture of (NH₄)Cl and Ca(OH)₂  is heated steam is formed and reach upper end of steam but when it liquefied come back at the bottom of test .It may cause cracking of test tube ,so hard glass test tube is slightly slanted to prevent of cracking .

                    Unit :- 11          Metals

Metal :The elements which have  a tendency to loss electrons and form cat ion are called metal .For example :Mg, Na, Ca, Al etc.

Properties of metals:

Physical properties:

i)Most of metals are solid at ordinary temperature ,except mercury ,it is found in liquid state .

ii)Most of metals are generally hard ,except Na, K, Li, they are soft .

iii)Metal posses metallic luster (shining)

iv)Metals have generally high density ,except Na, K ,Li.

v)Metal posses ductile property (i.e. can be change into wires)except Na, K, Li.

vi)Metals are generally good conductors of heat and electricity .

vii)The boiling and melting point of metals are high ,except Na, K, Li.

viii)Metals atoms generally contains 1,2,3,electrons to their valence shell .

ix)Metals are generally electropositive in nature because loss their valence electrons.

x)Metals possess malleability (i.e. can be beaten in thin plate)

Ores : The minerals from which metals can be extracted in large amount are  called ores.

Metallurgy :  The process by which the metals can be extracted from the ores is called metallurgy .There are 4 major steps in the extraction of metals (Metallurgy ) are as follows :

1)Mining : The process of taking out  ores from the mines is called mining .

2.)Crushing and pulverisation :The process of breaking big lumps of extracted ores into smaller pieces  hammering in a mill is called crushing .

The process of converting crushed ores into fine power state in a stamp mill is called pulverisation 

3.)Concentration :The process removing of the undesired foreign impurities from the ores is called concentration .

4.)Calcination and roasting : The process of converting concentrated ores into oxides by heating  to remove volatiles impurities i.e.CO₂ ,SO₂  and moister  etc. is called calcinations or roasting .

5.)Reduction of metal oxide into metal .

6.)Refining  or purification :

Some important metals :

1.)Iron

Symbol =Fe (Ferrum)

Atomic number (At .N.)=26

Atomic weight (At. Wt.)=56

Valency :2 (Ferrous)

                : 3 (Ferric)

Position in periodic table :Transition metal ,d-block elements ,4rth periods .

Ores :

i)Haematite (Fe₂O₃) : it is also called major ores of iron .

ii)Magnetite (Fe₃O₄)

iii)Iron carbonate (FeCO₃)

iv)Siderite

v)Limonite

vi)Iron pyrite 

Physical properties :

i)It is shiny and grayish white metal .

ii)It is malleable and ductile .

iii)It is good conductor of heat and electricity

Uses :

i)It is used for making different types of pipes rods ,and cable wires .

ii)It is used for making different types instruments and weapons .

iii)It is used for making building ,bridges ,and means of transportation i.e. bus, trucks etc.

iv) It is used for making different types of household utensils .

v) It is used for making steels .

2.) Aluminium

Symbol =Al (Aluminium)

Atomic number (At .N.)=13

Atomic weight (At. Wt.)=27

Valency :3

Position in periodic table : Group -IIIA ,P-block elements ,3rth periods .

Ores :

i)Bauxite =Al₂O_3.2H₂O :It is also called major ores of aluminium.

ii)Felspar =K((AlSiO_3.O₈)

iii)Cryolite

Physical properties :

i)It is shiny and silvery white metal .

ii)It is malleable and ductile .

iii)It is good conductor of heat and electricity

Uses :

i)It is used for making aluminium paint .

ii)It is used for making electric cable .

iii)It is used for making coins .

iv)Due to its malleable ,ductile and light properties it is used for making aeroplane .ship,car etc .

v)It is used for making household utensil  .

3.)Copper

Symbol =Cu (Cuprum)

Atomic number (At .N.)=29

Atomic weight (At. Wt.)=63.57

Valency :1 (Cuprous )

                 =2(Cupric)

Position in periodic table : Transition metal ,d-block elements ,4rth periods .

Ores :

i)Copper pyrite or chalcopyrite =CuFeS₂: it is also called major ore of copper .

ii)Chalcocite or copper glance =Cu₂S

iii)Cuprite (Ruby copper )

iv)Malachite

v)Azurite

Physical properties :

i)It is shiny and reddish brown metal .

ii)It is malleable and ductile .

iii)It is good conductor of heat and electricity.

 Uses:

i)It is used for making cables ,and electric appliances .

ii)It is used for making coins ,and brass .

iii)It is used for making household utensil.

iv)It is also used for making insecticide and pesticides .

4.)Silver

Symbol =Ag (Argentum)

Atomic number (At .N.)=47

Atomic weight (At. Wt.)=107.9

Valency :1

Position in periodic table : Transition metal ,d-block elements ,6^th  periods .

Ores :Gold is mostly found free state in nature due to less reactive nature ,so it is also called noble gas, but some important ores of gold are :

i)Alluvial soil

ii)Calaverite=AuTe₂

Uses of gold :

i)It is used for making jewelry and coins .

ii)It is used for making medals .

iii)It is used for making status.

iv) It is used for gold plating .

Aquarejia :Mixture of 3 parts of Conc HCl and 1 parts of Conc H(NO₃)is  called aquarejia .It produce nascent

Some ores of metal in Nepal .

i)Iron :Lalitpur ,Bhojpur,chitwan, Pyuthan

ii)Copper =Udayapur ,Makwanpur

iii)Gold= Rapti river,Mustang ,Kathmandu

iv)Manesium =Udayapur

v)Lead =Lalitpur

vi)Bismuth =Makwanpur

vii)Cobalt :Palpa

viii)Calcium =Lalitpur ,Kathmandu

ix)Zinc =Lalitpur

Arrangement of increasing reactivity

Al<Fe<Cu<Ag<Au

Arrangement of increasing density

 Al<Fe<Cu<Ag<Au

Arrangement of increasing melting point

Al<Ag<Au<Cu<Fe

           Unit :- 12   Hydrocarbon and its Compounds

Organic chemistry :The branch of chemistry concerned with the compounds of carbon is called organic chemistry .

Inorganic chemistry: The branch of chemistry concerned with the compound of elements other than carbon is called inorganic compound .

Differences between organic and inorganic compound :

Organic compound

Inorganic compound

i.)The compounds of carbon other than oxides of carbon ,carbonates, bicarbonates, and carbides are called organic compounds .

 

ii.)Organic compounds having low melting and boiling points .

iii.)Organic compounds burn easily .i.e. Ghee, alcohol 

iv)These are formed by covalent bond.

v.)Organic compounds are insoluble in water .

i.)The compounds other than compounds of carbon except oxides of carbon, carbonates ,bicarbonates ,and carbides are called inorganic compounds.

ii.)Inorganic compounds having high melting and boiling points

iii)Inorganic compounds do not burn easily . i.e. salt

iv)These  are formed by electrovalent bond.

v)Inorganic compounds are soluble in water .

 Hydrocarbon :The chemical compounds which is formed by the bonding between Hydrogen and carbon is called Hydrocarbon .

Types of Hydrocarbon :-They are two types .

1)Saturated hydrocarbon :The hydrocarbon in which carbon –carbon atoms combine with single covalent bond is saturated hydrocarbon .Its IUPAC (International union pure applied chemistry )is Alkane or Paraffins .

Alkane or Paraffin :A hydrocarbon in which carbon – carbon atoms combine with single covalent bond is called Alkane or paraffin .Its general formula is  C_n H_2n +2 where n= number of carbon atoms i.e. 1,2,3,4 etc. For example :

B.)Unsaturated hydrocarbon :The hydrocarbon in which carbon atoms combine with double  or triple covalent bond is called unsaturated hydrocarbon.Its  IUPAC (International union pure applied chemistry ) name is Alkene   and  Alkyne  .

Alkene  or  Olefins :A hydrocarbon in which carbon –carbon atoms combine with double covalent bond is called  alkene or olefins .For example :

Alkyne or Acetylene : A hydrocarbon  in which carbon –carbon atoms combine with triple covalent is called alkyne or acetylene .For example :

Catenation: The ability of carbon to combine with another carbon atoms to long chain of or ring of different size is called catenation .For example :

Allotropes :The property of a pure element having same composition but found in two or more than two forms in the same state is called allotropes .For example :

                                                         Allotropes of carbon

Homologous series :A group of hydrocarbon which contains the same functional group but  has the different CH₂ group or length is called homologous series For example : Homologous series of alkane i.e.

Methane

Ethane 

Propane

Butane

Pentane

Homologous series of Alkene i.e.

Ethene

Propene

Butene

Pentene

Hexene

Properties of homologous series :

i)All members of homologous series can be represented by the same general formula .

ii)All member of homologous series show similar chemical properties .

iii)All the members of homologous series can be prepared by similar method .

Isomers :Isomers are the organic compound having the same molecular formula but different structure and properties are called isomers .The process of existence of two or more organic compound having same molecular formula but different structure and properties is called isomerism .For example :

i)CH₃CH₂OH                           CH₃-O-CH₃

Ethyl alcohol                           Dimethyl ether

ii)CH₃-O-C₃H₇                                   C₂H₅-O-C₂H₅

     Methyl propyl ether          Diethyl ether

Properties of isomers :

i)Isomers have same molecular formula .

ii)Isomers have different structural formula

iii)Isomers have different physical and chemical properties .

Alkyl radical :The group of organic compound which is formed by removing  one hydrogen atoms from alkane For example :

i)CH_4⟶            ^-H           CH₃⁺   (Methyl radical )

ii)C₂H₆  ⟶                  ^-H       C₂H₅⁺   (Ethyl radical)

When alkyl group combine with functional group and form different types organic compounds .For example :

i)CH₃OH    (Methyl alcohol )

ii)C₂H₅-O-C₂H₅       (diethyl ether )

Functional group: An atom or group of atoms that determine the chemical properties of a hydrocarbon is called a functional group . For example : i)Hydroxyl -(OH) =formed alcohol ii)-O- Formed ether 

 When alkyl group combine with functional group and form different types of organic compound .

Some important hydrocarbon and their uses ;

A)Methane =CH₄

It is saturated hydrocarbon and formed during decomposition of organic matter i.e.vegetable ,animals matters .It is also called Marsh gas .It is found in marshy or swamp areas and natural gas and petroleum mine  .

Uses :

i)It is used as source of  fuel .

ii) It is used for making water gas and hydrogen gas .

iii)It is used making printing ink and paints .

iv) It is used for making chloroform, carbon tetrachloride ,methyl alcohol.

B)Ethane =C₂H₆

It is saturated hydrocarbon .It is found in natural gas ,coal and petroleum mine .

Uses:

i)It is used as source of fuel .

ii)It is used for making shoe polish, printer ink.

C)Propane = C₃H₈

It is a saturated hydrocarbon .It is found in natural gas ,and petroleum mines .

Uses : i)It is used as source of fuel .i.e.  in lighter.

ii)It is used in petroleum industries for cooling purpose .

D)Butane  =C₄H₁₀

It is saturated hydrocarbon .It is found in natural gas and petroleum mine .

i)It is used as source of fuel i.e. LPG (Liquefied petroleum gas)

ii)It is used for making raw material for making synthetic rubber .

E) Alcohol:  Organic compound having hydroxyl group (OH) is called alcohol . For example : Methyl alcohol , Ethyl alcohol etc .

Types of alcohol : On the basis of number of hydroxyl groups .They are 3 types :

1.)Monohydric alcohol :The alcohol which is formed replacement of single hydrogen atom of alkane by same number of hydroxyl group is called monohydric alcohol .For example :

2.)Di hydric alcohol : The alcohol which is formed replacement of two hydrogen atom of alkane by  same number of hydroxyl group is called dihydric  alcohol .For example :

3.)Tri hydric alcohol : The alcohol which is formed replacement of three hydrogen atom of alkane by  same number of hydroxyl group is called tri hydric alcohol .For example :

                 Example of some monohydric alcohol :

Some important alcohol :

1.)Methyl alcohol =CH₃OH

Uses :i)It is used as fuel in sprit lamp (Produce heat without smoke )

ii)It is used for making synthetic fibre.

iii)It is used to dissolve fat, oil  paints ,varnish .

Note: Consumption of methyl alcohol causes of blindness or death .

2.)Ethyl alcohol =C₂H₅OH :It is also called real alcohol .

Uses : i) It is used for making intoxicated drinks i.e. wine, beer, whisky etc.

ii)It is used in alcohol thermometer.

iii)It is used for making medicine, soap, synthetic rubber etc.

iv)It is used as preservatives for biological specimens .

Note :Consumption of ethyl alcohol  causes of effects  cerebellum so person losses balance .

3.)Glycerol =C₃H₅(OH)₃: The word glycerol derived Latin word   glyceros ,which means sweet , so it is also called colourless viscous liquid with sweet taste .

Uses :It is used as sweetening  agent .

ii) It is used for making medicine .

iii)it is used for making stamp pad ink .

iv)It is used for making high quality of soap, cosmetics lotions ,creams etc.

F) Glucose :The glucose word has been derived from Greek word glukus which means sweets in taste .Its molecular formula is C₆H₁₂O₆ .It is also called dextrose .It is used used by body to produce ATP .it is found in fruit and honey .Glucose is both harmful and useful for animals .

Uses : It is used for prepare Bakelite plastic .

ii)It is used as sterilizing agent .

iii)It is used for making formalin which is used as a preservative for biological specimen

                        Unit :- 13  Materials used in Daily Life

         

1)Cement :A mixture of calcium silicate and calcium aluminate is called cement .It is found in the form fine grey powder and when mixed with it change into hard mass like stone .

Lime stone + Clay →¹⁶⁰⁰    Cement clinker +carbon +water

Raw materials and steps of manufacturing cement :

Raw materials : i)Lime stone  (Ca(CO₃)

 ii) Clay soil  (Al₂O_3.SiO₂)

Steps :i)Crushing   ii)Grinding    iii)Finishing

Cement clinker :An initial state of cement like small red ball which is obtained after heating the complex mixture of calcium silicate and calcium aluminate  is called cement clinker .

 Cement clinker is cooled and 2-3 percent Gypsum is added ,because gypsum(CaSO₄.2H₂O) increase the setting  time of cement that from the crakes while plastering .

Process of manufacturing of cement :During manufacturing of cement ,At first one third parts of clay soil and two third parts lime stone powder is mixed with water to make a slurry ,then the slurry is sent through the top of a rotating kiln to the bottom .In the kiln mixture is heated to a temperature of 1600 .When it reaches at  the bottom it is known as cement clinker .Then about 2-3 percent of gypsum is added and grinded to produced cement .

Morter :A mixture cement ,sand , and water is called morter .It is used as plastering materials .

Concrete :A mixture of cement ,sand, water and gravels is called concrete .It is used for flooring and roofing .

RCC(Reinforcement cement concrete ):A mixture cement, sand ,water and gravel with iron frame is called RCC .It is used for making roofs and pillars .

Uses of cement :

i)It is used for making joining bricks ,plastering walls roofs etc .

ii)It is used for making concrete .

iii) It is used for making pillars ,roofs etc . 

2) Glass : An amorphous ,transparent homogenous mixture of silicate of alkali  metal or silicate of  earth alkaline  metal is known as glass .The main substance of glass is silica (silicon dioxide ) and main source is sand .

Si     + O₂       →            SiO₂ (Silica or Silicon dioxide )

Glass is a super cooled liquid or crystalline form of metal silicate so crystal molecules of glass flow slowly like liquid therefore glass in window pane after many years will look thick at the lower surface than that of the upper surface .

Types of glass :On the basis of chemical composition and components glasses are classified into following types :

1.)Quartz glass or silica glass :The glass which is formed by heating silica about 1600⁰C  is called quartz glass .It is also called crystalline glass .

SiO₂    →             ^{heating 1600}     SiO₂  (Pure silica)

Features :i)It is pure silica .

ii)It is hard and crystalline .

iii)It does not dissolve in water ,acid and other chemicals .

Uses :i)It is used for making lab. equipment, electrical appliance ,gems, colored quartz .

2.)Water glass :The glass which is formed by heating mixture of silica and carbonates of sodium and potassium under 800⁰c is called water glass .

SiO₂     + Na₂CO₃   800⁰c   →          Na₂(SiO₃)   +CO₂

                                                   Sodium silicate (water glass )

Features :

i)It is soluble  in water .

Uses :i) It is used in decoration i.e. making silica garden .

ii)It is used for making fire proof materials

iii)It is used in soap manufacturing and preserving eggs .

3.)Ordinary glass or Soda lime glass or  soft glass :The glass which is formed by heating mixture of 50% silica ,25% glass pieces ,15 % sodium carbonate ,and 10 % calcium carbonate under 1500 ⁰c is called ordinary glass .

But if little amount of lead monoxide is mixed in the mixture of ordinary glass before heating lead crystal or lead silicate  glass is obtained and also increases refractive index of glass .

SiO₂   +Na₂(CO₃) +Ca (CO₃)   →         Na₂(SiO₃).Ca(SiO₃) +2 CO₂

Features :i)It has very low thermal resistance .

ii)It is insoluble in water .

Uses :i)It is used for making bottle, window panes , and other useful  objects .

4.)Hard glass or potash lime glass :The glass which is prepared by heating silica with potassium carbonate and calcium carbonate is called Hard glass .

SiO₂  + K₂CO₃  + CaCO₃  →        K₂SiO_3.CaSiO₃  +CO₂

Features :It has high melting point .

ii)It is not affected by water and other chemicals .

Uses :It is used for making lab. apparatus i.e. beakers ,hard glass test tube, tube light etc .

5.)Borosilicate glass or pyrex glass :The which is prepared by heating silica with sodium carbonate, calcium carbonate and boric oxide is called borosilicate glass .

SiO₂ +Na₂CO₃ +CaCO₃+B₂O₃    →       NaSiO₃.CaSiO₃.B₂SiO₃ +CO₂

Features . i) It is not affected by water and chemicals .

ii)It is stronger than that of ordinary glass .

Uses :It is used for making lab .apparatus i.e. test tube, beaker ,flasks etc.

6.)Lead crystals glass  or flute glass :The glass which is prepared by heating  silica with potassium carbonate and lead monoxide is called lead crystals glass .

SiO₂ +K₂CO₃ +PbO      →         K₂SiO₃.PbSiO₃ + CO₂

Features :i)it has high refractive index .

Uses :It is used for making lab. apparatus i.e. hard glass test tube ,prism lens .etc.

ii)It is used to cut off UV radiation .

7.)Optical glass :The glass which is prepared by heating silica with potassium carbonate ,and red lead is called optical glass .

Features :it is has high refractive index .

Uses .i)It is used for making lens ,for camera ,telescope, spectacles etc .

Colored glass :The glass is made different colors by addition of following metals oxide :

S.N.	Color of glass	Metal oxide
1. 2. 3. 4 5. 6. 7.	Blue Black Green Purple Red White Yellow	Cobalt oxide Nickel oxide Cupric oxide , chromium oxide Manganese dioxide  Cuprous oxide Tin oxide Ferric oxide

3.)Fibers: The thread like substance possessing strength and elastic property is called fibers .

Types of fibers :There are 2 types fibers :

1.)Natural fibers :Naturally produced fibers are called Natural fibers .They are also two types :

i)Animals fibers :Wool, and silk are animals fibers .It is used for making clothes .

ii)Plant fibers :Cotton, Jute, bombax, hamp etc .It is used for making clothes ,sacks etc .

2.)Artificial fibers :Man made fibers are called artificial fibers They are also two types :

i)Recycled fibers :The artificial fibers made from cellulose present in cotton, and pulp of wood (soft fleshy part) are called recycled fibers or fiber made by mixing natural fiber and cellulose are called recycled fibers  .It is similar to that of cotton .For example :rayon.

ii)Synthetic fibers :The artificial fibers which are prepared by chemical process are called synthetic fibers .For example : Nylon, polyster, acrylene, olefiins etc . It is used for making carpets ,socks, vest ,threads, sweaters , and different types clothes .  

 

4.)Ceramics :The special types of clay which consist compounds of carbon, nitrogen, oxygen, and silica is called ceramics .Ceramics is a hydrated aluminum silicate (Al₂O_3,SiO₂.2H₂O) .The clay which is used to make white ceramics is called kaolin .In other words ,the pure white clay which is used to make cup, plate etc. is called Kaolin .

Method of preparation of ceramics :In order to make ceramics at first ,The soil is mixed with water and molded into different shapes ,then it is dried in the sun light and heated in furnace at high temperature ,due to chemical reaction the soil harden but become porous .So at last slat glaze are spray on it to make it shiny, non porous, and smooth.

Features  or nature of ceramics :

i)It has attractive smooth surface .

ii)It disperse equal amount of heat all around its surface.

iii)The object of ceramics are not affected by acid, base, salt and high temperature .

iv)It is insulator of heat and electricity .

v)It can use at very temperature .

Uses :

i)it is used for making household materials i.e. jugs, pots, cups, etc.

ii)It is used for making electric insulator .

iii)It is used for making furnace to at high temperature .

iv)It is used for making artificial teeth, bone joints etc .

5.) Plastics :

Monomer :The smallest unit of organic compound that can be polymerized to get polymer is called monomer. For example :Ethene

Polymer :A long chain of organic compound that is produced from the process of polymerization is called polymer .For example :Polythene

Polymerization :The process by which monomers are converted into polymer is called polymerization .

Types of polymers :They are two types :

1.)Natural polymers :The naturally produced polymers are called natural polymers .For example : Protein, cellulose ,starch .rubbers etc .

2.)Plastic or artificial polymer :The polymers which are made human being from the polymerization of carbon containing monomers  is called plastics .

Characteristics of plastics : Plastics materials are used more than other materials due to following properties :

i)They are light and can be molded into different shape.

ii) It is cheap ,durable, and bad conductors of heat and electricity .

iii)It has chemical resistance i.e. acid ,base, and salt .

iv)It can colored easily and made transparent .

Types of plastics : There are two types of plastics :

1.)Thermo plastics	2.)Thermo setting plastics
i)The plastics which can be changed into various shapes by heating is called thermo plastics . ii)It melt when is heated and become solid when it is cooled. iii)It can be used again –again by heating .For example :Poly vinyl chloride (PVC),Polyester ,Polythene, Nylon etc.	ii)The plastics which can not be changed into various shapes by heating is called thermo plastics . ii)It become much harder but does not melt  when it is heated iii)It can not be used again –again by heating .For example :bakelite ,Melamine etc.

 Some plastics :

i)Bakelite :Bakelite is a thermosetting plastics .It is prepared by condensation and polymerization of formaldehyde and carbolic acid .It is used for making handle of cooker ,plugs, switch, buttons etc .

ii)Melamine :Melamine is a thermosetting plastics .It is used for making cup, plates, bowls etc.

iii)Poly vinyl chloride (PVC):PVC is thermo plastics .It is prepared by polymerization of vinyl chloride .It is used for making curtain, rain coat, etc.

Uses of plastics :

i)Plastics are used for making furniture, tunnels, and motors parts etc.

ii)They are used for making motors, aeroplane ,water tanks ,pipes etc.

iii)They are used for making clothes ,shoes, bags, sacks etc.

iv)They are used for insulation of electrical appliances and heating devics.

Bad effects or disadvantages of plastics :

i)They are non bio-degradable.

ii)They easily catch fire .

iii)They causes of air ,water, and soil pollution 

6.) Soap and Detergent :

Soap :The sodium salt of long chain of fatty acid having cleansing properties in water  is called soap . For example :i)Sodium stearate (C₁₇H₃₅COONa)    ii)Sodium Oleate (C₁₇H₃₃COONa),     iii) Sodium Palmitate (C₁₇H₃₁COONa)

 

It is prepared by heating fat or oil with sodium hydroxide solution .

The process of making soap by hydrolysis of fat or oil with sodium hydroxide or alkali is called  saponification .

 

Detergents :Synthetic petrochemical obtained from hydrocarbon which is more soluble than soap is called detergent .It is more soluble and useful than that of salt .Detergent possess  cleansing properties similar to the soap but they are not chemically soap therefore detergents are also called soapless  soap .For example :i)Sodium lauryl sulphate    ii) Alkyl benzene sulphonate  iii)Sodium pyrophosphate .

Due to following reasons detergent is better than that of salts :

i)Detergent clean more effectively in hard water than that of soap .

ii)It maintains its cleansing power better than that of soap over long period of time .

iii)It is more soluble in water than that soap .

iv) It also help to save vegetable oil for human consumption .

Washing powder  :A synthetic powder having cleansing properties containing synthetic detergent about 15%-30% is called washing powder

Differences between Soap and Detergent

Soap	Detergent
i)It is prepared from animals  fat or plants oil . ii)It is sodium salt of long chain of fatty acid . iii)It has weak cleansing properties . iv)it is very less soluble in hard water . v)It is bio-degradable . v)For example :Sodium stearate	i)It is prepared from hydrocarbon of petroleum . ii)It is sodium salt of long chain of benzene sulphonic acid . iii)It is has strong cleansing properties . iv)It is soluble in hard water . v)It is non bio-degradable . vi) For example :Sodium lauryl sulphonate.

 

7.)Insecticides :-The chemical substances which are used to kill harmful insect is called insecticides.

Types of insecticides :They are two types

1.)Organic insecticides :The insecticide which are containing carbon are called organic insecticides. It also contains hydrogen ,oxygen, chlorine  and, phosphorous. On the basis of chlorine, phosphorous, and  carbomate  organic insecticides are also divided into 3 types :

A)Organo –Chlorine :The organic  insecticides which contains chlorine as principle element is called organ chlorine .For example :i)DDT =Dichloro diphenyl  trichloro ethane

ii)BHC =Benzene Hexa chloride

iii)Dieldrin

iv)Aldrin

B)Organo-Phosphorous :The organic insecticide which contains phosphorous as principle elements is called Ogano-phosphorous .For example :i)Malathion  ii)Parathion

C)Carbomate :The organic insecticide which contains amino group(NH₂) as principle element is called carbomate .For example :i)Baygon   ii)Turmic

2.)Inorganic insecticide :The insecticides which are made up from minerals or inorganic compound is called inorganic insecticides. For example :i)Lead arsenate  ii)Calcium arsenate  iii)Lime sulpher   iv)Floride

It is used to protect fruits ,vegetables ,cotton etc.

Advantages of insecticides :

i)They are used to control or kill harmful insects .

ii)They also help to control diseases.

Disadvantages of insecticides:

i)Insecticides kill harmful insecticide as well as useful insecticide .

ii)They are non bio-degradable so causes of soil,air and water pollution .

8.)Fertilizer :The substances which added to the soil to increase the fertility of the soil are called fertilizer .It help provide  the necessary elements to the plants .

Types of fertilizers :-They are two types :

1)Organic fertilizers: The fertilizers which are obtained from dead and decomposed parts of animals and plants or their waste product are called organic fertilizer . There are also two types of organic fertilizers :-

i)Green organic fertilizers :The organic fertilizer which are prepared by cutting green plants and later which are decomposed under soil are called green organic fertilizer or green manure .These types of fertilizer mainly provides  nitrogen  to the plants in form of nitrates .

ii)Compost manure  :-The organic fertilizer which are prepared from dead and decayed and decomposed  parts of plants  animals and their waste product  are called animal organic fertilizer .

Method of preparation of compost manure :It is prepared by mixing of cattle dung,rotten vegetable ,straw etc. in a pit .Some time lime is also added to make a good fertilizer .It is left in a pit to decay for some month by the action of microorganism and the mixture gets decomposed into the compost manure .

Advantages of organic fertilizers :

i.)It help to Balances the soil ecosystem

ii)It help plant to make health naturally

iii)They’are all-natural .

iv)It increase the fertility of soil.

 v)It does not  affect the quality of soil.

vi)It controls environmental pollution.

 vii)Prevents from  over-fertilization

Disadvantages of organic fertilizers:

i)It requires more  time to be  prepared. so effectiveness is limited seasonally.

ii)It is insoluble in water and it is difficult to transport from one place to another place .

iii) Nutrients ratio is always unknown .

2.)Chemical fertilizers or inorganic fertilizers: The fertilizer which are made by mixing different  of chemicals substances are called chemical fertilizers .They are mainly contains nitrogen, phosphorus and calcium elements.

N.P.K fertilizers :The fertilizer containing  all three nutrients i.e. Nitrogen(N) ,Potassium (K) and calcium(Ca) essential for plants is called NPK fertilizers .It is also called complete fertilizer.

 Advantages of chemical or inorganic fertilizers :

i)Inorganic  fertilizer increase the fertility of the soil.

ii)They have special types of nutrients .

iii)They can transport easily .

iv)They are water soluble ,so plants can absorb easily .

Disadvantages of inorganic or chemical  fertilizers :

i)Inorganic fertilizer pollute the environments.

ii)Inorganic fertilizers increase the fertility of the soil.

Some important inorganic fertilizers :  On the basis of three basic  elements fertilizer are divided into three types :

1.)Nitrogeneous  fertilizer :The chemical fertilizer that supply nitrogen to plants are known as nitrogeneous fertilizer For example :

i)Urea (NH₂CONH₂)

ii)Ammonium suplhate  (NH₄)₂(SO₄)

iii)Ammonium nitrate (NH₄)(NO₃)

Functions of Nitrogen :

i)It help in rapid growth in plants .

ii)It help to increase yield (to give way) of growth .

iii)Sufficient nitrogen help for high rate of photosynthesis .

iv)It help in the formation of chlorophyll ,carbohydrate protien, and protoplasm .

Deficiency of Nitrogen :

i)Due to lack of nitrogen plants will be shorter ,leaves may be smaller and maturity of plants may be delayed too .

ii)Shortage of nitrogen will causes of yellowing of leaves .

iii) Due to lack of nitrogen rate of photosynthesis will decreases and less branching in plants .

2.)Phosphatic  fertilizer :The fertilizers that supply phosphorus to the plants are called phosphatic fertilizers .For example :

i)Calcium super phosphate

ii)Triple super phosphate

iii)Bone metal .

Functions of Phosphorus :

i)It help in early maturity  and ripening of fruits,and grains or seeds  .

ii)It help in formation and fast growth of root .

iii)It help in formation of seeds and increase resisting diseases .

Deficiency  of phosphorus :

i)Due to lack of phosphorus flowering may be delayed .

iii)Due to lack of phosphorus reduces diseases resistant power of the plants .

3.)Potash fertilizers :The fertilizers that supply potassium to plants are known potash fertilizers .For example :

i)Potassium chloride (KCl)

ii)Potassium sulphate  K₂(SO₄)

iii)Potassium carbonate K ₂(CO₃)

iv) Potassium Nitrate    K (NO₃)

Functions of potassium :

i)It help in the utilization of nitrogen and help in protein synthesis .

ii)It help for making healthy roots and shoots .

iii)It also help to increase resist against diseases

iv)It help to regulates the opening and closing of stomata . 

Deficiency of potassium :

i)Lack of potassium causes of poor resistance for  diseases.

ii)Lack of potassium causes of weak roots and shoots.

iii)Lacks of potassium causes of losing of leaves .

9.)Chemical pollution :The environmental degradation due to unscientific and improper uses of chemical substances is called chemical pollution .

Causes of chemical pollution :

1.)Uses of insecticides and chemical fertilizer :It causes of air ,water and soil pollution ,different diseases ,the death of fishes and other aquatic life .

2.)Household wastage and plastics :The toxic substances present in wastage causes of air ,water ,and soil pollution and produce poisonous gases burning .

3.)Uses of coloring materials in food stuff :It  causes of dangerous diseases i.e. cancer .

4.)Products of smokes vehicles  and industries :It causes of air pollution of air and different diseases .

5.)Uses of synthetic cleaner (detergent ):It causes of rapid growth of weeds and algae in water due to lack of oxygen in water as result aquatic animals begin to die .

Methods of controls of chemical pollution :

i)By scientific and proper uses of insecticides and fertilizer .

ii)By management of household wastages and plastics .

iii)By management of smoke produce  by vehicles and industries .

iv)By less uses of coloring materials in food stuff .

v)By management of uses of synthetic cleaner .

 

10.)Solid wastage :The unwanted or unusable wastage from industrial ,commercial ,agriculture operation ,and community activities are called solid wastage .They are two types :

A) Bio-degradable solid wastage :The solid wastage which can be degraded by living organism i.e. bacteria ,fungi and a biotic elements i.e. temperature ,ultra violet ray and oxygen etc are called bio-degradable solid wastage ..For example :waste parts of plants, death body of animals ,paper, clothes ,wastage foods etc .

B)Non-bio-degradable solid : The solid wastage which can not be degraded by living organism i.e. bacteria ,fungi and a biotic elements i.e. temperature ,ultra violet ray and oxygen etc are called Non- bio-degradable solid wastage .For example :Plastics ,wastage of glass ,iron ,bottle of glass etc.

Steps of managements of solid wastage :

i)By collection and transportation

ii)By segregation and waste management

iii)By processing and disposal .

iv)By landfill dumping

v)By incineration :The most dangerous and poisonous solid wastage are brunt at high temperature i.e. 500⁰C- 1200⁰C in special types of furnace .This process is called incineration .