F.sc. Part 1 Chemistry Chapterwise Test Solved by Malik Xufyan

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CHEMISTRYCHEMISTRYCHEMISTRY
Chapter-wise
Test Series
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Chapter # Topic Page #
Basic concepts – Unsolved paper1
2
3
4
5
6
7
8
9
10
11
5
6
16
17
24
25
36
37
45
46
54
55
64
65
73
74
83
84
93
94
103
104
Experimental Techniques – Solved Paper
Gases – Unsolved Paper
Gases – Solved Paper
Liquid – Unsolved Paper
Liquid – Solved Paper
Atomic Structure – Unsolved Paper
Atomic Structure – Solved Paper
Chemical Bonding –Unsolved Paper
Chemical Bonding – Solved Paper
Thermochemistry – Unsolved Paper
Thermochemistry – Solved Paper
Chemical Equilibrium – Unsolved Paper
Chemical Equilibrium – Solved Paper
Solu on – Unsolved Paper
Solu on – Solved Paper
Electrochemistry – Unsolved Paper
Electrochemistry – Solved Paper
Chemical Kine cs – Unsolved Paper
Chemical Kine cs – Solved Paper
Basic concepts – Solved Paper
Experimental techniques – Unsolved Paper
INDEX

Chapter#1: Basics Concepts Malik Chemistry
Jhang Institute for Advanced Studeies6
Name : CH # Basic Concepts Class 11th
Chemistry-1 Test # 01 , CH # 01 (Complete) Marks : 85
Time : 2 & Half Hour Objective & Subjective JIAS Text System
Section-l: Objective
Choose the correct answer 17 x 1=17
Sr
#
Statement A B C D
1. The phenomenon of isotropy was discov-
ered by
Dalton Berzelius Soddy Boltzmann
2. Tin has isotopes 3 9 11 none
3. 11.0 gm of CO2
contains molecules 6.02 x1023
3.01 x 1023
1.505 x 1023
none
4. The percentage of oxygen in NaOH 16 32 40 60
5. In combustion analysis water vapours are
absorbed in
50 % KOH Mg(ClO4
)2
NaOH MgCl2
6 The SI unit of pressure is atm psi Newton per me-
ter square
None
7. Isotopes differ in Properties which
depend upon mass
Arrangement of
electrons in orbit-
als
Chemical prop-
erties
None
8. The mass of one mole of electron is 0.5 mg 1.008mg Both None
9. 27 gm of AL reacts completely with how
many mass of oxygen to produce aluminium
trioxide
8 gm of oxygen 16 g of oxygen 24 g of oxygen None
10. The number of moles of carbon dioxide
which contains 8.0gm of oxygen
0.25g 0.50 g 1 g 1.5g
11. A limiting reactant is the one which Is taken in lesser
quantity in gm as
compared to other
reactants
Is taken in lesser
quantity in volume
as compare to oth-
er reactant
Gives the maxi-
mum amount of
product which is
required
Give minimum
amount of product
under consider-
ation
12. A full stop may have ….atoms present in it 2 lac 20 lac 20 million None
13. Which of the following is equal to mole Gram atom Gram formula Gram ion All
14. Which of the following element is used for
making 50 percent of earth crust
Mg Si Fe All
15. If we are given the mass 0f one substance
we can calculate the volume ,this is called
Mass-mass relation-
ship
Mass volume re-
lationship
Mass mole None
16. Atomic mass may be given in Fractions Decimal Integers None
17. Atomic masses are the…..masses Average Actual Total All

Jhang Institute for Advanced Studeies 7
Section-ll: Short Question
1. Attempt only EIGHT questions 8
x 2= 16
i. Justify that 23 g of Na and 238 g of uranium have
equal no. of atoms?
ii. Why law of conservation of mass has to be obeyed
during stichiometric calculations?
iii. What is relative atomic mass? Give its significance?
iv. No individual atom in the sample of element has a
mass of 20.18 amu.
v. One mg of K2
Cr2
O7
has thrice the number of ions than
the number of formula units when ionized in water.
vi. Mg is twice heavier than that of carbon of atoms in
them,
vii. Justify many chemical reactions taking place in our
surrounding involve the limiting reactant.
viii. Calculate the moles of Cl atoms in 0.822 g of C2
H4
Cl.
ix. Define gram atom and molar volume with three ex-
amples.
x. Define stoichiometry and gram formula with three
examples.
xi. N2
and CO have the same number of electrons, pro-
tons and neutrons.
xii. 180 g of glucose and 342 g of sucrose have the same
number of molecules but different number of atoms
present in them.
2. Attempt any 8 questions 8 x 2 = 16
i. Atomic masses may be in fractions why?
ii. Define molecule .what are cationic molecular ions?
Give examples.
iii. What is combustion analysis and give formulas for
empirical formula determination.
iv. What are isotopes? Give examples.
v. What is the function of magnetic field?
vi. What is molecular formula? Give formula.
vii. Why we use atomic mass unit? Also define mole.
viii. Masses and the size of molecules do not affect the
volume why?
ix. Tell the contributions of Berzelius and Dalton?
x. Give the principal of mass spectrometry?
xi. What is limiting reactant? Give two reasonable ex-
amples?
xii. Formation of positive ion is endothermic process.
Justify it.
3. Attempt any 6 questions 6 x 2 =12
i. What are the limitations of chemical equation?
ii. What type of relationships can be studied with the
help of balanced chemical equation? What are the
conditions of stoichiometric calculations?
iii. How can we identify limiting reactant?
iv. Why we take one of the reactants deliberately in ex-
cess?
v. Differentiate between actual yield and theoretical
yield?
vi. What is Avogadro number?
vii. Why the formation of uni negative ion is an exother-
mic reaction?
viii. How molecular ions can be generated?
ix. How limiting reactant can be used to control the
amount of product?
x. Why actual yield is always less than theoretical yield?
Section-lll: Long Questions. 8 x 3 = 24
Attempt any 3 questions.
5) (a) What is empirical formula? What are the steps
included in the calculation of empirical formula?
(b) Ascorbic acid contains 40.92% carbon, 4.58% hy-
drogen and 54.5 % of oxygen by mass, what is the em-
pirical formula of ascorbic acid ?
6) (a) Silicon carbide (SiC) is an important ceramic ma-
terial. It is produced allowing sand (SiO2
) to react
with carbon at high temperature.
SiO2
+ 3C SiC + 2CO
When 100 kg sand reacted with excess of
Carbon, 51.4kg SiC is produced. What is
percentage yield of SiC?
(b) Write a detailed note on limiting reactant.
(a) Mg metal reacts with HCl to produce hydro-
gen gas. What is the minimum volume of HCl
solution (27 % by weight) required to produce
12.1 g of H2
. The density of HCl solution. is
1.14g/cm3
Cl2
+E Mg + 2HCl MgCl2
+ H2
(b) How empirical formula can be calculated from
combustion analysis?
(a) How can you determine of relative atomic masses
of isotopes by Mass spectrometry?
(b) Ethylene glycol is used as automobile antifreeze. It
has 38.7 % carbon, 9.7 % hydrogen and 51.6 % oxygen.
Its molar mass is 62.1 grams mol-1
. Determine its em-
pirical formula.
7) (a) Define Yield. How do we calculate the percentage
yield of a chemical reaction? What are factors which
are mostly responsible for the low yield of products
in chemical reactions?
(b) A well known ideal gas is enclosed in a container
having 500 cm3 at S.T.P. its mass comes out to be 0.70
g. what is the molar mass of this gas.

Section-ll: Short Questions
2. Attempt only EIGHT questions 8 x 2= 16
i. Justify that 23 g of Na and 238 g of uranium have equal no. of atoms.
Ans:
According to mole and Avogadro’s Number concept:
23 g of Na =1 mole of Na = 6.02x1023
atoms of Na
238g of U =1 mole of U = 6.02x1023
atoms of U.
Since equal number of gram atoms( moles) of different elements contain equal number of atoms.
Hence, 1 mole (23 g) of sodium and 1 mole (238 g) of uranium contain equal number of atoms, i.e,
6.02 x1023
atoms.
ii. Why law of conservation of mass has to be obeyed during stoichiometric calculations?
Ans:
According to law of conservation of mass: the amount of each element is conserved in a chemical
reaction. Chemical equations are written and balanced on the basis of law of conversation of mass.
Stoichiometry calculations are related with the amounts of reactants and products in a balanced chem-
ical equation. Hence, law of conservation of mass has to be obeyed during stoichiometric calculations.
iii. What is relative atomic mass? Give its significance?
Ans:
Relative atomic mass:
Relative atomic mass is the mass of an atom of an element as compared to the mass of atom of carbon
taken as 12.
Significance:
The masses of the atoms are extremely small. We don’t have any balance to weigh such an extremely
small mass, that is why we use the relative atomic mass unit.
iv. No individual atom in the sample of element has a mass of 20.18 amu.
Ans:
According to the average atomic mass:
Since the overall atomic mass of neon in the average of the determined atomic masses of individual
isotopes present in the sample of isotopic mixture. Hence, no individual neon atom in the sample has
a mass of 20.18 amu.
Calculation:
v. One mg of K2
Cr2
O7
has thrice the number of ions than the number of formula units when ionized
in water.
Ans:
K2
Cr2
O7
when ionizes in water produces two k+
ions one Cr2
O7
ion. Thus each formula unit of K2
Cr2
O7
produces three ions in solution .Hence one mg of K2
Cr2
O7
has thrice the number of ion than the
number of formula units ionized in water.

2 ions + 1 ion = 3 ions
vi. Mg is twice heavier than that of carbon of atoms in them.
Ans:
The atomic mass of Mg is 24 which is twice as mass as compared to the atomic mass of carbon One
gram atom of different elements has different mass. One mole of carbon is 12g, while one mole of
magnesium is equal to 24 g.It means that one atom of Mg is twice in mass than one atom of carbon.
vii. Justify many chemical reactions taking place in our surrounding involve the limiting reactant.s
Ans:
According to the definition of limiting reactant:
A limiting reactant is one which has limited quantity and consumed first in a chemical reaction.
In our surrounding many chemical reactions are taking place which involve oxygen. In these reactions
oxygen in always in excess quantity while other reactant are in lesser amount.Thus other reactants act
as limiting reactants.
Example:
1. Petrol burns in excess of oxygen present in air
2. Rusting of iron in the excess of oxygen present in air.
viii. Calculate the moles of Cl atoms in 0.822 g of C2
H4
Cl.
Ans:
Mass = m = 0.822 g
Cl-atoms = ?
Molecular mass of C2
H4
Cl2
= 12 x 12 + 1 x 4 + 35.5 x 2
= 99
No. of moles of C2
H4
Cl2

= 8.30 x 10 -3
1 mole of C2
H4
Cl2
= 2 moles of Cl-atoms
8.30 x 10 -3
moles of 8.30 x 10 -3
= 2 x 10-3
x 8.30
= 0.017 moles of Cl-atoms
ix. Define gram atom and molar volume with three examples.
Ans:
Gram Atom:
The atomic mass of an element expressed in grams is called gram atom of an element.
For example:
1 gram atom of Hydrogen = 1.008 g
1 gram atom of Carbon = 12.00 g
1 gram atom of Uranium = 238 g
Molar volume: The volume occupied by one mole of an ideal gas at standard temperature and pres-
sure (STP) is called molar volume. The volume is equal to 22.414 dm3
.
Example
1 mole of H2
=6.02 x 1023
molecules of H2
= 2.06 g of H2
= 22.414 dm3
at S.T.P
x. Define stoichiometry and gram formula with three examples.
Ans:
Stoichiometry:
Stoichiometry is the branch of chemistry which gives a quantitative relationship between reactants
and products in balanced chemical equation.
Assumptions:
1. All the reactant are the completely changed in to the products.
2. While doing calculations law of conservation and law of definite proportions are obeyed.

3. There is no side reaction
Gram fomula:
The formula mass of an ionic compound expressed in grams is called gram formula of the substance.
Formula:
Example
1 gram formula of NaCl = 58.50 gt
1 gram formula of Na2
CO3
= 106 g
1 gram formula of AgNO3
= 170 g
Assumptions: N2
and CO have the same number of electrons, protons and neutrons.
Ans:
For N2
:
In N2
there are 2 N atoms which contain 14 electrons (2 x 7)
14 protons (2 x 7) and 14 neutrons (2 x 7)
For CO:
In CO, there are one carbon and one oxygen atoms.
It contains 14 electrons (6 carbon’s electron +8 oxygen’s electrons)
14 protons (6 C protons + 8 O proton)
and 14 neutrons (6 neutrons + 8 O neutrons).
For CO & N2
:
Hence, N2
and CO have the same number of electrons, protons and neutrons.
Remember that electrons, protons and neutrons of atoms remain conserved during the formation of
molecules in a chemical reaction.
xi. 180 g of glucose and 342 g of sucrose have the same number of molecules but different number of
atoms present in them.
Ans: According to mole and Avogadro’s Number:
180 g of glucose = 1 mole of glucose = 6.02x1023
molecules of glucose
342 g of sucrose = 1mole of sucrose = 6.02x1023
molecules of sucrose
Since one mole of different compounds has the same number of molecules.
Therefore,1 mole (180 g) of glucose and I mole (342 g) of sucrose contain the same number (6.02x1023
)
of molecules.
While one molecule of glucose (C12
H22
O11
) contains 45 atoms and one molecules of glucose
(C6
H12
O6
) contains 24 atoms.
Therefore, 6.02x1023
molecules of glucose contain different atoms as compound to 6.02x1023
molecules
of sucrose.
Hence, 180 g of glucose and 342 g of sucrose have the same number of molecules but different number
of atoms present in them.
i. Atomic masses may be in fractions why?
Ans: Atomic masses of elements show many examples of fractional values. Actually the atomic mass-
es depend upon the number of possible isotopes and their abundance.
Neon atom in the sample has a mass of 20.18 amu.
Calculation:

ii. Define molecule .What are cationic molecular ions? Give examples.
Ans:
Molecule:
A molecule is the smallest particle of a pure substance (element or compound) which can exist inde-
pendently.
Example:
N2
, O2
, Cl2
, HCl, NH3
and H2
SO4
are examples of molecules.
Cationic molecular ions:
In chemical terms, if a neutral molecule loses one or more electrons, it carry positive charge and is
known as cationic molecular ion.
Example:
For example, when ammonia (NH3
) accepts a proton (H+
), it forms the ammonium ion (NH4
+
).
iii. What is combustion analysis and give formulas for empirical formula determination.
Ans:
Those organic compounds which simply consists of carbon, hydrogen and oxygen can be analyzed by
combustion. The sole product will be CO2
and H2
O. These two products of combustion are separately
collected.
Empirical formula is determined by combustion analysis by these formulas:
iv. What are isotopes? Give examples.
Ans:
Isotopes:
Atoms of the same element which have different masses but same atomic numbers are called isotopes.
Example:
For example carbon has three isotopes.
12
C6
13
C6
14
C6
and expressed as C–12, C–13 and C–14.
Similarly hydrogen has three isotopes 1
H, 2
H, 3
H called protium, deuterium and tritium.
v. What is the function of magnetic field?
Ans:
when ions are allowed to pass through a strong magnetic field of strength (H), which will separate
them on the basis of their (m/e) values, actually magnetic fields makes ions to move in a circular path.
vi. Wh at is molecular formula? Give formula.
Ans:
Molecular Formula:
The formula of a substance which is based on the actual molecule is called molecular formula. It gives
the usual number of atoms present in the molecule.
Example:
For example molecular formula of benzene is C6
H6
, while that of glucose is C6
H12
O6
. The molecular
formula and empirical formula are related to each other by the following relationship.
Molecular formula = n x (Empirical formula)
Where “n” is simple integer.

vii. Why we use atomic mass unit? Also define mole.
Ans: The masses of the atoms are extremely small. We don’t have any balance to weight such an ex-
tremely small mass. That’s why we use the relative atomic mass unit scale.
Mole: The molecular mass of a substance expressed in grams is called molecule or gram mole or
simply the mole of a substance.
Examples:
1 mole of water = 18.0 g
1 mole of H2
SO4
= 98.0 g
viii. Masses and the size of molecules do not affect the volume why?
Ans:
According to the definition of molar volume:
It is very interesting to know from the above data that 22.414 dm3
of each gas has a different mass but
the same number of molecules. The reason is that masses and the size of molecules do not affect the
volume. Normally, it is known that in the gaseous state the distance between molecules is 300 times
greater than their diameters and due to large distance between atoms in molecule, size and mass does
not affect on the volume. We ignore it due to large distance between atoms in molecule.
ix. Tell the contributions of Berzelius and Dalton?
Ans:
Berzelius Contributions:
(1) ASwedish chemist J. Berzelius determined the atomic masses of elements. A number of his values
are close to the modern atomic masses.
(2) Berzelius also developed the system of giving element a symbol.
Dalton Contributions:
Dalton developed an atomic theory; the main postulate of which is that all matter is composed of at-
oms of different elements, which differ in their properties.
x. Give the principal of mass spectrometry?
Ans:
Principle: In this technique, a substance is first volatilized and then ionized with the help of high
energy of beam of electrons. The gaseous positive ions, thus formed, are separated on the basis of
their mass to charge rate (m/e) and then recorded in the form of peaks. Actually mass spectrum is the
plot of data in such a way that (m/e) is plotted as abscissa (x-axis) and the relative number of ions as
ordinate (y-axis).
xi. What is limiting reactant? Give two reasonable examples?
Ans:
Limiting reactant:
A limiting reactant is a reactant and that controls the amount of the product formed in a chemical
reaction due to its smaller amount.
1st
Example: A larger quantity of oxygen in a chemical reaction makes things burn more rapidly. In
this way excess of oxygen is left behind at the end of reaction and the other reactant is consumed ear-
lier. This reactant which is consumed earlier is called limiting reactant.
2nd
Example: the concept of limiting reactant is analogous to the relationship between the number of
‘’kababs’’and the slices to prepare ‘’sandwiches’’. If we have 30 ‘’kababs’’ and five breads ‘’having
58 slices ‘’, then we can only prepare 29 ‘’sandwiches’’. One ‘’kabab’’ will be extra (excess reactant)
and slices will be limiting reactant.
xii. Formation of positive ion is endothermic process. Justify it.
Ans:
The electrons in an atom are being attracted by the nucleus. So an electron can only be removed from

the atom, if energy is supplied so that it overcomes the attractive forces of the nucleus.
Hence for the formation of cation (positive ion) energy is always given to the electron present in an
atom.
(Endothermic Process)
i. What are the limitations of chemical equation?
Ans:
Limitations of Chemical Equations:
Chemical equations have certain limitations as well.
1. They do not tell about the conditions and the rate of reaction.
2. Chemical equations can even be written to describe a chemical change that does not occur.
ii. What type of relationships can be studied with the help of balanced chemical equation? What
are the conditions of stoichiometric calculations?
Ans:
There are three types of relationships of stoichiometric calculations.
1. Mass–Mass Relationship:
The relationship in which the mass of one substance is given and the mass of other substance is cal-
culated.
3. Mass–mole or mole–mass relationship:
The relationship in which mass of one substance is given and moles of other substance is to be calcu-
lated or vice versa.
4. Mass-Volume or Volume mass relationship.
The relationship in which the mass of one substance is given and the volume of other substance is to
be calculated or vice versa.
Conditions of Stoichiometry:
a) Reactants are completely converted into products
b) No side reactions occurs
c) While doing calculations, the law of conversion of mass and the law of definite proportion are
obeyed.
iii. How can we identify limiting reactant?
Ans:
To identify a limiting reactant, the following three steps are performed
1. Calculate the number of moles from the given amount of reactant.
2. Find out the number of moles of product with the help of a balance chemical equation.
3. Identify the reactant which produces the least amount of product as limiting reactant.
iv. Why we take one of the reactants deliberately in excess?
Ans:
1. Often, in experimental work, one or more reactants are deliberately used in excess quantity. The quan-
tity exceeds the amount required by the reaction’s stoichiometry. This is done, to ensure that all of the
expensive reactant is completely used up in the chemical reaction.

2. Sometimes, this strategy is employed to make reaction occur faster.
v. Differentiate between actual yield and theoretical yield?
Ans:
vi. What is Avogadro number?
Ans:
Definition:
Avogadro’s number is the number of atoms, molecules and ions in one gram atom of an element, one
gram molecule of a compound and one gram ion of substance. These are 6.02 x 1023
Representation
It is represented by NA
. Its value is 6.02 x 1023
.
Example
Mass of sodium = 23 grams = 1mole = 6.02 x 1023
atoms
Mass of uranium = 238 g = 1 mole = 6.02 x 1023
atoms
vii. Why the formation of uni-negative ion is an exothermic reaction?
Ans:
Energy is usually released when an electron is added to the isolated neutral atom. Therefore, the for-
mation of an uninegative ion is an exothermic process.
The most common negative ions are F-
, Cl-
, Br-
etc.
(Exothermic process)
viii. How molecular ions can be generated?
Ans:
These ions can be generated by passing high energy electron beam as α-particles or X-rays through a
gas. (P.T.B page # 3)
ix. How limiting reactant can be used to control the amount of product?
Ans:
A limiting reactant is a reactant and that controls the amount of the product formed in a chemical
reaction due to its smaller amount.
A larger quantity of oxygen in a chemical reaction makes things burn more rapidly. In this way excess
of oxygen is left behind at the end of reaction and the other reactant is consumed earlier. This reactant
which is consumed earlier is called limiting reactant.
x. Why actual yield is always less than theoretical yield?
Ans:
There are three basic reasons:
(a) A practically inexperienced worker has many shotcomings and cannot get the expected yield.
(b) The processes like filtration, separation by distillation, separation by a separating funnel, washing,

drying and crystallization if not properly carried out, decrease the actual yield.
(c) Some of the reactants might take part in a competing side reaction and reduce the amount of de-
sired product.
Section-lll: Long Questions (8 x 3 = 24)
5) (a) What is empirical formula? What are the steps included in the calculation of empirical formu-
la?
Ans:
See The Text Book Page # 7-8
(b) Ascorbic acid contains 40.92 percent carbon, 4.58 percent hydrogen, and 54.5 percent of oxygen
by mass, what is the empirical formula of ascorbic acid?
See The Text Book Page # 8 Example # 3
5) (a) Silicon carbide is an important ceramic material; it is produced allowing sand to react with
carbon at high temperature.
When 100 kg sand reacts with excess of carbon 51.4 kg SiC is produced. what is percentage yield
of SiC?
Ans:
See the Text Book Page # 29, Q.22
(b) Write a detailed note on limiting reactant.
Ans: see the Text Book Page # 20-21
6) (a) Mg metal reacts with HCl to produce hydrogen gas. what is the minimum volume of HCl soln.
(27 percent by weight) required to produce 12.1 g of H2
.the density of HCl soln. is 1.14g/cm3
Ans:
See The Text Book Page # 19, Example # 12
(b) How Empirical formula can be calculated from combustion analysis?
Ans:
7) (a) How can you determine of relative atomic masses of isotopes by Mass spectrometry?
Ans:
(b) Ethylene glycol is used as automobile antifreeze. It has 38.7 % carbon, 9.7 % hydrogen and
51.6 % oxygen. Its molar mass is 62.1 grams mol-1
. Determine its empirical formula.
Ans:
See The Text Book Page # 28, Q.16
8) (a) Define Yield. How do we calculate the percentage yield of a chemical reaction? What are fac-
tors which are mostly responsible for the low yield of products in chemical reactions?
Ans:
See the Text Book Page # 22
(b) A well known ideal gas is enclosed in a container having 500 cm3
at S.T.P. its mass comes out
to be 0.70 g. what is the molar mass of this gas.
Ans: See The Text Book Page # 17 , Example # 10

Chapter#2: Expermental Techniques Malik Chemistry
Jhang Institute for Advanced17
Name : CH # Experimental Techniques Class 11th
Chemistry Test # 02 , CH # 02 (Complete) Marks : 85
Time : 2 & Half Hour Objective & Subjective JIAS Test System
Section-I: Objectives
1. Choose the correct answer.
Sr # Statement A B C D
1. A quantitative determination
involves
2 steps 3 steps 4 steps None
2. Ninhydrin acid is used for Locating agent Stationary phase Spraying phase Mobile phase
3. A chemical characterization of a
compound must include
Q u a l i t a t i v e
analysis
Quantitative
analysis
Both None
4. The filter paper is a porous material
used for
Contraction Filtration Extension None
5. Whatmann grade filter paper is
used for
Paper
chromatography
Column
chromatography
Partition Descending
6 Thin film of absorbed water on
cellulose act as
Stationery phase Mobile phase Mixed phase None
7. The solid remained on the filter
paper during filtration is called
Molecule Photon Residue Proton
8. Rate of filtration can be increased
using
Desiccators Cold finger All
9. The most common solvent use for
solvent extraction in lab is
Ether Water Filter paper Ethanol
10. In paper chromatography stationary
phase
Gas Water Filter paper None
11. The drying agents used in vaccum
desicator are
CaCl2
Silica gel All None
12. A fluted filter paper can Increase the rate
of filtration
Decrease the
rate of filtration
Stop the
filtration
Have no effect
13. Size of filter paper is selected
according to
Precipitates Solution Solid particles Water
14. The result of qualitative and
quantitative analysis is called
Analytical data Continuous data C o m p o u n d
data
Discrete data
15. Solvent extraction is an equilibrium
process and is controlled by
Law of mass
action
Partition law Amount of
solute
None
16. The word chromatography
originates from
Chromatos Kharomatos Both None
17. No preparation is needed in Gooch crucible Sintered glass
crucible
Both Filter paper

Chapter#2: Expermental Techniques Malik Chemis-
Section-ll: Short questions
i. How vacuum desiccators are used to dry the
crystals?
ii. Give the main uses of paper chromatogra-
phy?
iii. Name various techniques which are used for
the purification of substance?
iv. Why is there a need to crystallize the crude
products?
v. What is chromatography? Give its origin?
vi. What is Rf value? Give its formula?
vii. What is solvent extraction?
viii. What is distribution law?
ix. What is Gooch crucible?
x. What is filtration?
2. Attempt only SIX questions 6 X 2 = 12
i. Define sublimation with an example.
ii. Differentiate between adsorption and parti-
tion chromatography.
iii. Define mother liquor? How the crystals can
be obtained from mother liquor?
iv. Rate of filtration through funnel can be in-
creased by using a fluted filter paper why?
v. How decolonization of undesirable colour
is done?
vi. What is the role of stationary phase in chro-
matography?
vii. What are the characteristics of an ideal sol-
vent?
viii. Which solvents are mostly used for crys-
tallization?
ix. How crystals are collected?
i. How filter paper is folded?
ii. Differentiate between quantitative and qual-
itative analysis.
iii. Why repeated extraction is preferred?
iv. What is chromatogram?
v. What is solvent front?
vi. Filter the saturated solution when hot .why?
vii. Define analytical chemistry?
viii. What is the most common solvent in
solvent extraction method? Why we choose
ether in solvent extraction?
ix. What is the principle of chromatography?
x. What is the importance of distribution coef-
ficient?
xi. Name the different ways of paper chroma-
tography.
5) Write a detailed note on solvent extraction?
6) What is chromatography also differentiating
between adsorption and partition chroma-
tography?
7) Write a detailed note on
a) Drying of the crystallized substance
b) Decolourization of the undesirable colours.
8) Write a note on paper chromatography.
9) Write a detail about crystallization and
choice of solvent?

2. Attempt only Eight questions 8x2=16
i. How vacuum desiccators are used to dry the crystals?
Ans:
A safe and reliable method of drying crystals is through a vacuum desiccator. In this process the crys-
tals are spread over water glass and kept in a vacuum desiccator for several hours. In the desiccators
CaCl2
, silica gel or P2
O5
are used as drying agents.
ii. Give the main uses of paper chromatography?
Ans.
Use of Chromatography
• The techniques of chromatography are very useful in organic synthesis for separation, isolation, and
purification of the products.
• Mostly used for the separation of amino acids.
iii. Mention the major steps in crystallization?
1. Choice of solvent
2. Preparation of saturated solution
3. Filtration
4. Cooling
5. Collecting the crystals
6. Drying the crystallized substance
7. Decolonization of undesirable colours
iv. Name various techniques which are used for the purification of substance?
Ans:
Techniques:
1. Filtration
2. Crystallization
3. Sublimation
4. Solvent Extraction.
5. Chromatography.
v. Why is there a need to crystallize the crude products?
Ans:
When a chemical compound is synthesized, it is crude product. Crude product has some impurities.
Therefore, there is need to purify the crude product. This is done by crystallizing the compound.
vi. What is chromatography? Give its origin?
Chromatography:
It is a technique used for separating the components of a mixture. These components are separated due
to the relative affinity for stationary phase and mobile phase.
Origin:
The word chromatography originates from the Greek word ‘’Khromatos’’ meaning colour writing.
vii. What is Rf
value? Give its formula?
Ans:
Rf
: Each component has specific retardation factor called Rf
value. Rf
value is related to distribution
coefficient and is given by

viii. What is solvent extraction?
Ans:
Solvent extraction:
That a solute distributes itself between two immiscible liquids in a ratio irrespective of the amount of
solute added.
The ratio of the amounts of solute dissolved in two immiscible liquids at equilibrium is called distribu-
tion coefficient.The technique of solvent extraction is mostly applied to separate organic compounds
from water.
ix. What is distribution law?
Ans:
Distribution law:
This law states that a solute distribute itself between two immiscible liquids in a ratio irrespective of
the amount of solute added.
The ratio of the amounts of solute dissolved in two immiscible liquids at equilibrium is called distribu-
tion coefficient.
x. What is Gooch crucible? How is differentiate between Sintered Glass Crucible?
Sr # Gooch crucible Sintered crucible
1.
A Gooch crucible has a perforated
bottom that supports a fibrous mat.
Sintered-glass crucibles are manufactured in fine,
medium, and coarse porosities.
2.
The reagents which react with paper
e.g. HCl, KMnO4
etc. cannot be filtered
through Gooch crucible
But reactive solution like HCl, KMnO4
can be
filtered with the sintered crucible
3.
Glass mats can tolerate temperatures in
excess of 500°C and are substantially
less hygroscopic.
The upper temperature limit is usually ~200°C.
Small circles of glass matting are used
in pairs to protect against breaking
during the filtration
Made of quartz and can tolerate substantially higher
temperatures without damage. A Gooch crucible
has a perforated bottom that supports a fibrous mat
xi. What is filtration?
Ans:
Filteration:
The process in which the insoluble particles are separated from the liquid by passing through several
types of filter media is called filtration. It is used to purify products.
4. Attempt only SIX questions 6 x 2 = 12
i. Define sublimation with an example.
Ans:
Sublimation:
When substance is heated it goes directly in to vapours without passing through the liquid state and va-
pours thus formed are condensed back it form the solid on cooling once again without passing though
liquid state is called sublimation.

Example: Iodine, NH4
Cl, naphthalene,Anthracene, benzoic acid are best examples for sublimation process
ii. What is adsorption chromatography?
Sr # Adsorption chromatography Partition Chromatography
1. Type of Chromatography in which
the stationary phase is solid, called
adsorption chromatography.
Type of Chromatography in which the
stationaryphaseisliquid,iscalledadsorption
chromatography.
2. Example of this chromatography is Thin
layer chromatography.
Example of this chromatography is paper
chromatography.
iii. Define mother liquor? How the crystals can be obtained from mother liquor?
Ans.
Mother liquor:
The remaining solution after the formation of crystals is called mother liquor.
Steps for obtaining crystals from mother liquor:
1. The mixture of crystals and mother liquor is filtered through a Gooch crucible connected with a vacu-
um pump.
2. After full suction to drain the mother liquor as effectively as possible. When the filter is rigid enough
it is pressed carefully but by firmly by means of a cork in order to drain the left over liquid.
3. The crystals are then washed will small portion of cold solvent repeating this process many times.
4. The crude mother liquor is concentrated by evaporation and it get good crops of crystals.
iv. Rate of filtration through funnel can be increased by using a fluted filter paper why?
Ans.
A fluted filter paper is prepared by folding ordinary filter paper in such a way that fan like arrangement
with alternate elevation and depression at various folds is formed.
v. How decolonization of undesirable colour is done?
Ans:
Sometimes during the preparation of crude substance, the colouring matter or resinous products affect
the appearance of product and it may appear coloured. Such impurities are conveniently removed by
boiling the substance in a solvent with the sufficient quantity of finely powdered animal charcoal and
the pure decolourized substance crystallizes out from the filtrate on cooling.
vi. What is the role of stationary phase in chromatography?
Ans:
Role of stationary phase:
The phase over which mobile phase flows in chromatography is called stationary phase.
The stationary phase may be a solid or liquid supported on a solid. It adsorbs the mixture under sepa-
ration.
Examples of stationary phase are silica gel, alumina and filter paper etc.
vii. What are the characteristics of an ideal solvent?
Ans:
Characteristics:
A solvent should have the following characteristics
1. It should dissolve a large amount of solute in its boiling part.
2. It should have no reaction with the solute.
3. It should neither dissolve the impurities, nor crystallize them with the solute.

4. It should be perfectly safe to use.
5. It should be easily removable.
6. It should be inexpensive.
viii. Which solvents are mostly used for crystallization?
Ans:
The solvents which are mostly used for crystallization are, water, rectified spirit, (95% ethanol), abso-
lute ethanol, diethyl ether, acetone, chloroform, carbon tetrachloride, acetic acid and petroleum ether.
ix. How crystals are collected?
Ans:
Collecting the Crystals:
When the crystallization is complete, then mixture of crystals and mother liquor is filtered through
Gooch crucible using a vacuum pump. The mother liquor is removed completely by full suction. Then
the filter cake is pressed to remove the rest mother liquor. Finally the crystals are washed with small
amount of cold solvent. This process is repeated many times till pure crystals are formed. By evapora-
tion of the mother liquor we can get a fresh crop of crystals.
3. Attempt any 8 x 2 =16
i. What is fluted filter paper?
Ans:
A filter paper which is fan like arrangements with alternate elevations and depressions at various folds.
ii. How filter paper is folded?
Ans:
1) Filter paper should be folded twice. The first fold should be along the diameter, and the second fold
should be such that edges do not quite match.
2) Folded filter paper should be open slightly on the larger section. This provides a cone with three fold
thickness half way and one thickness the other half way round.
3) The apex angle is greater than 60o
.
4) The paper may be inserted in to 60 degree funnel moistened with water and firmly pressed down.
iii. What are the steps of quantitative determination?
Ans:
Steps:
There are 4 steps:
a) Obtaining a sample for analysis
b) Separation of the desired constituent
c) Measurement and calculation of results
d) Drawing conclusion from the analysis
iv. Differentiate between quantitative and qualitative analysis.
Ans:
Sr # Qualitative analysis Quantitative analysis
1. The analysis which deals with the detection
or identification of the elements present in
a compound is called qualitative analysis.
It includes salt analysis and detection of
functional groups.
The analysis in which the relative
amounts of constituents are estimated is
called quantitative analysis. For example
combustion analysis.
2. It includes salt analysis and detection of
functional groups.
For example combustion analysis

v. Why repeated extraction is preferred?
Ans:
Repeated extractions using small portions of solvent (ether) are more efficient than using single but
larger volume of solvent. The technique is partially useful when the product is volatile or thermally
unstable.
vi. What is chromatogram?
Ans: Finished or Developed paper obtained after Chromatography is called Chromatogram:
vii. What is solvent front?
Ans: Solvent front:
The line where the solvent ends on the plate is called the solvent front and it changes with time.
viii. Filter the saturated solution when hot .why?
Ans: The hot saturated solution is filtered to remove insoluble impurities. Sometimes premature crystals
can form. It can be prevented by using hot water funnel.
ix. Define analytical chemistry?
Ans: The science of chemical characterization is called analytical chemistry.
x. What is the most common solvent in solvent extraction method? Why we choose ether in solvent
extraction?
Ans: The common solvent is ether in the solvent extraction we choose ether in the solvent extraction
because ether layer is separated and organic product is obtained by evaporating ether repeated ex-
tractions using small portions of solvent ether are more efficient than using single but larger volume
of solvent.
xi. What is the principle of chromatography
Ans.Principle:
The principle involved in the chromatography depends upon the relative solubilities of the compo-
nents, between the two phases. The distribution of the components mixture between the two phases is
governed by the distribution coefficient KD
, which is ratio of component in mobile phase to the con-
centration of component in stationary phase.
xii. What is the importance of distribution coefficient?
Ans. The component of a mixture with a small value of KD
mostly remains in the stationary phase as mov-
ing phase flows over it.
The component with a greater value of KD
remains largely dissolved in the mobile phase and passes
over the stationary phase quickly.
xiii. Name the different ways of paper chromatography.
Ans. Kinds of Paper Chromatograpy:
There are three ways of carrying out paper chromatography.
a) Ascending chromatography
b) Descending chromatography
c) Radial/Circular chromatography.
5) Write a detailed note on solvent extraction?
6) What is chromatography also differentiating between adsorption and partition chromatography?
7) Write a detailed note on
a) Drying of the crystallized substance
b) Decolourization of the undesirable colours.
8) Write a note on paper chromatography.
9) Write a detail about crystallization and choice of solvent?

Chapter#3:Gases Malik Chemistry
Name : CH # Gases Class 11th
Chemistry Test # 03 , CH #03
(Complete)
Marks : 85
Section 1: Objective
1. Choose the correct a nswer
1. Plasma is conductor of electricity Poor Bad Good None
2. The value of R is 8.214 8.314 Both None
3. The law which correlates the volume and
temperature of a gas is called
Boyle law Charles law Avogadro
law
Graham law
4. The temperature at which the volume of a
gas theoretically becomes zero is called
Absolute
temperature
Critical
temperature
Transition
temperature
Normal
temperature
5. Both Celsius and Fahrenheit scales are
intercontertable by using the formula
F=1.8o
C+32 F=1.8o
C-40 F=1.8o
C+212 None
6 Which of the following matters does not
show diffusion?
Solids Liquids Gas All
7. Diffusion of different species is due to
difference of
Potential energy Density Temperature All
8. ……. of known universe is in the plasma
state
59 % 99 % 5 % 2 %
9. Which of the following gas is ideal at
-200o
C?
nitrogen Helium Both None
10. Real gases deviate from the ideal behavior
at very
High pressure Low
temperature
Low pressure Both a and b
11. Which of the following expression is right? V= m/d PM = dRT PV = nRT All
12. Plasma is known as the 3rd
state of
matter
4th
state of
matter
2nd
state of
matter
None
13. The phenomenon in which sudden
expansion of a gas causes cooling is called
Joule Thomson
effect
evaporation Cooling sublimation
14. Density of a substance varies ……to
pressure at given temperature
Inversely Directly No change Can be any
15. Which of the following represents minimum
temperature
10 Centigrade 10 Fahrenheit 10 Kelvin All are equal
16. The colour of nitrogen dioxide is Yellow Green Brown Blue
17. The deviation of a gas from ideal behavior
is maximum at
-10o
C and 5atm -10o
C and
2atm
100o
C and
2atm
Oo
C and 2atm

i. Explain SO2
is comparatively non-ideal at 273 K but behaves
ideally at 327o
C.
ii. Explain water vapours do not behave ideally at 273 K.
iii. Explain the plot of PV versus P is a straight line at constant
temperature and with a fixed number of moles of an ideal gas.
iv. Hydrogen and helium are ideal at room temperature, but SO2
and Cl2
are non-ideal. How will you explain this?
v. How does kinetic molecular theory of gases explain the
Charles’s law?
vi. What do you know about aqueous tension?
vii. What is quantitative definition of Charles law also write formu-
la.
viii. Why Charles law is not being applied when temperature is mea-
sured on Celsius scale .also prove mathematically.
ix. Why -273.16 o
C are unattainable for real gases?
x. Why do we feel uncomfortable breathing at higher altitudes?
xi. Differentiate between diffusion and effusion of gas/
xii. What are the different values of ideal gas constant R? Derive its
value in SI units.
3. Attempt only 8 questions 8x2=16
i. Derive a relation for density of an ideal gas?
ii. What is an Avogadro LAW? Also explain graphically.
iii. What is Dalton’s la of partial pressure? Write mathematically.
iv. Why the mole fraction of mixture of anyone of gas is less than
unity?
v. The process of respiration can be explained by Dalton’s law
.how?
vi. State graham’s law of diffusion? Write formula.
vii. Write four points of kinetic molecular theory of gases.
viii. Which of the two points of kinetic theory of gases are faulty?
ix. Explain Avogadro’s law from kinetic theory of gases?
x. How heat flows from one body to another?
xi. What is the general principal of liquefaction?
4. Attempt any 6 questions 6x2=12
i. Define critical temperature and also write critical temperature
of some gases.
ii. What is joule Thomson effect?
iii. Why hydrogen and helium cannot be liquefied by Lind’s meth-
od of liquefaction?
iv. What is compressibility factor?
v. Why real gases deviate from ideality?
vi. How the various scales of thermometry can be inter- converted?
vii. Give some properties of gases?
viii. What is pressure? Give its different units.
ix. What are gas laws also state and derive Boyle’s law.
x. What is isotherm? Draw a graph of PV=K
Section-lll: Long Questions.
Attempt any three questions. 8 x 3 = 24
5) A) Write comprehensive note on plasma in detail?
b) Calculate the number of molecules and atoms
of methane gas taken at 0 O
c and 700mmHg
having volume 20 cm3
6) a) Derive van der waals equation for pressure correction.
b) 250 cm3
of the sample of hydrogen effuses four
times as rapidly as 250 cm3
of an unknown gas
.calculate the molar mass of an unknown gas?
7) a) Explain Lind’s method of liquefaction of gases also
draw diagram.
b) what pressure is exerted by a mixture of 2.00g of
H2
and 8.00g of N2
At 273K in a 10dm3
8) (a) What do you know about kinetic interpretation of
temperature?
(b) Calculate the masses of 1020
molecules of H2
, O2
and CO2
at STP. What will happen to the masses
of these gases, when the temperatures of these
gases are by 100 o
C and the pressure is decreased
by 100 torr.
9) (a) Write expression for pressure of an ideal gas By
R.J Clausius.
(b) 25 cm3
of the sample of hydrogen effuses four
times as rapidly as 250 cm3
of an unknown gas.
Calculate the molar mass of unknown gas
10) (a) What is Charles’s law? Explain it with experiment
and graphical explanation.
(b) A sample of krypton with a volume of 6.25 dm3
,
a pressure of 765 torr and a temperature of 20o
C
is expanded to a volume of 9.55 dm3
a pressure
of 375 torr. What will be its final temperature?

Section-Il: Short questions
2) Attempt only EIGHT questions 8 x 2= 16
i. Explain SO2
is comparatively non-ideal at 273 K but behaves ideally at 327o
C.
Ans:
At low temperature, the molecules of SO2
possess low kinetic energy. They come close to each other.
The intermolecular attractive forces become very strong. So, it behaves non-ideally at 273K.
At high temperature, the molecules of SO2
have high kinetic energy. The molecules are at larger dis-
tances from one another. The intermolecular attractive forces become very weak. So, it behaves ideally
at 327 K.
ii. Explain water vapours do not behave ideally at 273 k.
Ans:
Water vapors present at 273K do not behave ideally because polar water molecules exert force of attrac-
tion on one another. The intermolecular forces become strong.
iii. Explain the plot of PV versus P is a straight line at constant temperature and wit a fixed number of
moles of an ideal gas.
Ans:
At constant temperature and with a fixed number of moles of an ideal gas, when the pressure of the gas
is varied, its volume changes, but the product PV remains constant. Thus,
P1
V1
= P2
V2
= P3
V3
Hence, for any fixed temperature, the product PV when plotted against P. A straight line parallel to
P-axis is obtained. This straight line indicates that PV remains constant quantity.
iv. Hydrogen and helium are ideal at room temperature, but SO2
and Cl2
are non-ideal. How will you
explain this?
Ans:
Hydrogen (B.P: 253 o
C) and helium (B.P: 269 o
C)have a very low boiling points. They are far away
from their boiling points at room temperature. Also, they have smaller number of electrons in their
molecules and smaller molecular sizes, i.e., molecular weight. So, intermolecular forces are negligible
at room temperature. Hence, they behave as an ideal gases at room temperature.
On the other hand, SO2
(B.P:10 o
C) and C12
(B.P: 34 o
C) have boiling points near to room temperature.
They are not far away from their boiling points at room temperature. Also, they have larger number of
electrons in their molecules and larger molecular sizes. So, sufficient intermolecular attractive forces
are present at room temperature. Hence, they behave as non-ideal at room temperature.
v. How does kinetic molecular theory of gases explain the Charles’s law?
Consider the equation which has just been derived
vi. What do you know about aqueous tension?
Ans:

Aqueous tension:
Some gases are collected over water in the laboratory. The gas during collection gathers water vapours
and becomes moist. The pressure exerted by this moist gas is, therefore, the sum of the partial pressures
of the dry gas and that of water vapours. The partial pressure exerted by the water vapours is called
aqueous tension.
Formula:
Pmoist
= pdry
+ p w.vapour
Pmoist
= pdry
+ aqueous tension
Pdry
= Pmoist
- aqueous tension
vii. What is quantitative definition of Charles law also write formula.
It is quantitative relationship between temperature and volume of a gas and was give by French Scien-
tist J.Charles in 1787. According to this law, the volume of the given mass of a gas is directly propor-
tional to the absolute temperature when the pressure is kept constant.
Formula:
viii. Why Charles law is not being applied when temperature is measured on Celsius scale .Also prove
mathematically.
Ans:
Charles Law was defined on the basis of Kelvin scale. Because the value of k will not remain constant
on different temperatures if temperature is measured on Celsius scale.For example, if hypothetical gas
is warmed on different scale of temperature.
For Kalvin Scale For Celsius Scale
That’s why Charles law is not being applicable when temperature is measured on Celsius scale due to
above example in column.
ix. Why -273.16 o
C are unattainable for real gases?
Ans:

This temperature will be attained when the volume becomes zero. But for a real gas the zero volume is
impossible which shows that this temperature cannot be attained for a real gas. Actually, all the gases
are converted into liquids above this temperature. If real gas is converted into liquid at this temperature
then volume of gas cannot be zero.
x. Why do we feel uncomfortable breathing at higher altitudes?
Ans:At higher altitude, the pilots feel uncomfortable breathing because the partial pressure of oxygen in
the un-pressurized cabin is low as compared to 159 torr, where one feels comfortable breathing.
xi. Differentiate between diffusion and effusion of gas.
Ans:
Sr # Diffusion Effusion
1. Spontaneously intermixing of
molecules of one gas with another at
a given temperature and pressure is
called diffusion.
Effusion of a gas is movement through an
extremely small opening into region of low
pressure.
2. NO2
and O2
are intermixed
homogeneously after reacting them.
Effusion is when molecules escape from
their container into the space only when
they happen to hit the hole.
xii. What are the different values of ideal gas constant R? Derive its value in SI units.
Ans: If the pressure is expressed in mm of mercury or torr and the volume of the gas in cm3
then values
of R are :
R = 0.0821 dm3
atm K-1
mol-1
= 0.0821 x 760 dm3
mm Hg K-1
mol-1
= 62.4 dm3
mm Hg K-1
mol-1
since (1 mm of Hg =1 torr)
= 62.4 dm3
torr K-1
mol-1
= 62400 cm3
torr K-1
mol-1
since (1dm3
= 1000 cm3
)
Using SI units of pressure, volume and temperature in the general gas equation, the value of R is calcu-
lated as follows. The SI units of pressure are Nm-2
and of volume are m3
. By using Avogadro’s principle
1 atm = 7600 torr = 101 Nm-2
1 m3
= 1000 dm3
n = 1 mole
T = 273.16 K
P = 1 atm = 101325 Nm-2
Putting their values, alongwith units
3) Attempt only 8 questions 8 X 2 = 16
i. Derive a relation for density of an ideal gas?
Ans: for idea gas:

This equation is another form of general gas equation that may be employed to calculate the mass of a gas
whose P,T,V and molar mass are known. Rearranging equation:
Hence the density of an ideal gas is directly proportional to its molar mass.
ii. What is an Avogadro LAW? Also explain with example.
Ans:
Avagadro’s law : it states that
‘’ equal volume of the ideal gases at the same temperature and pressure contain equal number of mol-
ecules’’.
Example:
22.414 dm3
of a gas at 273.16 K and one atmospheric pressure has number of molecules = 6.02 x 1023
iii. What is Dalton’s law of partial pressure? Write mathematically.
Ans:
Dalton law of partial pressure:
John Dalton studied the mixture of gases his law of partial pressure. It states that:
‘’The total pressure exerted by a mixture of non-reacting gases is equal to the sum of their individual
partial pressures.’’
Mathematically:
Let the gases are designed as 1,2,3 and their partial pressure are p1
,p2
,p3
. The total pressure (P) of the
mixture of gases is given by
Pt
= p1
+ p2
+ p3
iv. Why the mole fraction of mixture of anyone of gas is less than unity?
Ans:
Because mole fraction of a component is the ratio of mole of component to the total number of moles
and we know that total number of moles are always greater than any of its component. So the formula
of mole fraction tells us the small value (of component) is divided by large value (total no .of moles) an
answer comes always equal to less than 1.
v. The process of respiration can be explained by Dalton’s law .how?
Ans:
Dalton law finds its applications during the process of respiration. The process of respiration depends
upon the difference in partial pressure. When animals inhale air then oxygen moves into lungs as the
partial pressure of oxygen in the air is 149 torr, while the partial pressure of oxygen in the lungs 116
torr, CO2
produced during respiration moves out in the opposite directions, as it’s partial pressure is

more in the lungs than that in air.
vi. State graham’s law of diffusion? Write formula.
Ans.
Thomas Graham, an English scientist, found that the rate of diffusion or effusion of a gas is inversely
proportional to the square root of its density at constant temperature and pressure.
Formula:
vii. Write four points of kinetic molecular theory of gases.
Ans:
Points of KMT:
1) The actual volume of molecules of a gas is negligible as compared to the volume of the gas
2) The molecules of a gas have not forces of attraction for each other
3) The molecules of a gas are very widely separated from one another and the sufficient empty spaces
among them.
4) Every gas consists of a large number of very small particles called molecules. Gases like He , Ne, Ar
have mono-atomic molecules
viii. Which of the two points of kinetic theory of gases are faulty?
Ans:
Faulty Points of KMT:
• The molecules of a gas have not forces of attraction for each other
• The actual volume of molecules of a gas is negligible as compared to the volume of the gas
ix. Explain Avogadro’s law from kinetic theory of gases?
Ans:
Avogadro’s law from KMT:
Consider two gases 1 and 2 with N1
& N2
(number of molecules), m1
& m2
are masses respectively.

According to kinetic equation:
Equalizing

when the temperature of both gases is the same, their mean kinetic energies per molecules will also be
same, so
Divide the equation (a) by (b)
N1
= N2
Hence , equal volume of all the ideal gases at the same temperature and pressure contain equal number
of molecules which is Avogadro’s law.
x. How heat flows from one body to another?
Ans:
When heat flows from one body to another, the molecules in the hotter body give up some of their
kinetic energy through collision to molecules in the colder body. This process of flow of heat continues
until the average translational kinetic energies of all the molecules become equal.
xi. What is the general principal of liquefaction?
Ans:
The conversion of a gas into a liquid requires high pressure and low temperature. High pressure brings
the molecules of a gas close to each other. Low temperature deprives the molecules from kinetic energy
and attractive forces start dominating.
For every gas there exist temperatures above which the gas cannot be liquefied, no matter how much
pressure is applied. The highest temperature at which a substance can exist as liquid is called its critical
temperature.
4) Attempt any 6 questions 6 x 2 =12
i. Define critical temperature. Also write critical temperature of some gases.
Ans:
Critical temperature:
The highest temperature, at which a substance can exist as a liquid, is called its critical temperature (Tc
).
Critical temperature of gases:
Water : 374.44 o
C
Oxygen : 118.75 o
C
Nitrogen : 147.06 o
C
Ammonia : 132.44 o
C
ii. What is joule Thomson effect?
Ans:
Definition:
When a compressed gas is allowed to expand into a region of low pressure it gets cooled.
The molecules of the compressed gas are very close to each other and appreciable attractive forces a
represent among term. When a gas is allowed to undergo sudden expansion through the nozzle of a

jet, then the molecules move apart. In this way energy is needed to overcome the intermolecular attrac-
tions. This energy is taken from the gas itself, which is cooled.
iii. Why hydrogen and helium cannot be liquefied by Lind’s method of liquefaction?
Ans:
Gases can be liquefying with the help of critical temperature. The value of critical temperature of Rea-
son a gas depends upon its size, shape and intermolecular forces present in it.
Helium and Hydrogen are small sizes gases.
Due to their very very small size as compared to other gases, these gases exist almost no force of attrac-
tion between their molecules .Hence they cannot be liquefied by Lind’s method.
Lind’s method is based on the Joule-Thomson’s effect. The liquefaction temperature of H2
is -252.7 o
C
and that of He is -268 o
C. These temperatures are very close to -273.16 o
C which is difficult to attain.
That’s why H2
and He cannot be liquefied by the Lind’s method.
iv. What is compressibility factor?
Ans:
Compressibility factor:
A graph is plotted between pressure on x-axis and on y-axis for an ideal gas. The factor is called
compressibility factor. Its value is unity under all conditions for an ideal gas. Since the increase of pres-
sure, the volume in such a way that remains constant at a constant temperature so straight line is
obtained parallel to the pressure axis.
i. Why real gases deviate from ideality?
Ans:
There are two basic reason:
a) When the pressure on a gas is high and the temperature is low then the attractive forces among the
molecules significant, so the ideal gas equation PV = nRT does not hold, actually under this condition
gas does not remain ideal.
b) The actual volume of the molecules of a gas usually very small as compared to the volume of the vessel
and hence it can be neglected. However, this volume does not remain negligible when the gas is sub-
jected to high pressure.
ii. How the various scales of thermometry can be inter- converted?
Ans:
Conversions: These are three conversion of scale of temperature
K= o
C + 273.16
o
C = [o
F – 32 ]
o
F = (o
C) + 32
iii. Give some properties of gases?
Ans:
Properties of gases:
a) Gases don’t have definite volume and occupy all the available space. The volume of a gas is the volume

of the container.
b) They don’t have definite shape and take the shape of the container just like liquids.
c) Due to low densities of gases as compared to those of liquids and solids, the gases bubble through liq-
uids and tend to rise up.
d) Gases can diffuse and effuse. This property is negligible in solids but operates in liquids as well.
e) The intermolecular forces in gases are very weak.
iv. What is pressure? Give its different units.
Ans:
Pressure:
It is the force exerted by 760 mm or 760 cm long column of mercury on an area of 1 cm2
at 0 o
C.
Units:
1) Atmosphere 2) torr
3) pascal 4) millibar
5) pounds inch-2
6) kilopascal
7) pounds per square 8) Nm-2
v. What are gas laws also state and derive Boyle’s law.
Gas laws:
The relationship between volume of a given amount of a gas and the prevailing conditions of tempera-
ture and pressure are called gas laws. Gas laws describe uniform behavior of gases.
Boyle’s law:
the volume of a given mass of a gas at constant temperature is inversely proportional to the gas.

V=
PV = k (when T and n are constant)
For initial and final condition
P1
V1
= k
P2
V2
= k
P1
V1
= P2
V2
Where
P1
V1
= initial condition
P2
V2
= final condition
vi. What is isotherm? Draw a graph of PV=K.
Ans:
The P-V curves obtained at constant temperat are called isotherms. These curves are ob-
tained by plotting a graph between pressure on the x-axis and volume on the y-a

Pressure (atm)
Volume (dm3
)
Isotherm at Oo
C
X
Y
Section-ll: Long Questions.
Attempt any three questions 8 x 3 = 24
5) a) Write comprehensive note on plasma in detail?
b) Calculate the number of molecules and atoms of methane gas taken at 0O
c and 700 mmHg having
volume 20 cm3
6) a) Derive van der waals equation for pressure correction.
b) 250 cm3
of the sample of hydrogen effuses four times as rapidly as 250 cm3
of an unknown gas.
Calculate the molar mass of an unknown gas?
6) a) Explain Lind’s method of liquefaction of gases also draw diagram.
b)what pressure is exerted by a mixture of 2.00g of H2
and 8.00g of N2
at 273 K in a 10dm3
7) (a) What do you know about kinetic interpretation of temperature?
(b) Calculate the masses of 1020
molecules of H2
, O2
and CO2
at STP. What will happen to the masses
of these gases, when the temperature of these gases are by 100 o
C and the pressure is decreased by
100 torr.
8) (a) Write expression for pressure of an ideal gas By R.J Clausius.
(b) 25 cm3
of the sample of hydrogen effuses four times as rapidly as 250 cm3
of an unknown gas.
Calculate the molar mass of unknown gas
9) (a) What is Charles’s law? Explain it with experiment and graphical explanation.
(b) A sample of krypton with a volume of 6.25 dm3
, a pressure of 765 torr and a temperature of 20o
C
is expanded to a volume of 9.55 dm3
a pressure of 375 torr. What will be its final temperature?

Chapter#5: Atomic Structure Malik Chemistry
Name : CH # Atomic Structure Class 11th
Chemistry Test # 05 , CH # 05 (Complete) Marks : 85
Section-1: Objective
Choose the correct answer 17 x 1=17
1. The nature of cathode rays depends upon Nature of electrode Nature of
discharge tube
Nature of
residual gas
All
2. When 6d orbital is complete ,entering electron
goes into
7f 7s 7p 7d
3. The nature of positive rays depends on Voltage applied Nature of
discharge tube
Nature of
electrode
Nature of
residual gas
4. If an elecrtron is free from attraction of nucleus
then its energy is
Negative Positive Zero None of these
5. Gases conduct electricity at High pressure Ordinary pressure Low pressure Normal
pressure
6 The quantum number which describes the
shape of an orbital is called
Principal quantum
number
Azimuthal
quantum number
Magnetic
quantum
number
Spin quantum
number
7. Quantum number values for 2p orbital are N=2, l=1 N=1,l=2 N=1 l=0 N=2,l=0
8. Lymann series lies in UV region Visible region IR region None of these
9. Photons of green colour are more energetic than
those of
Violet color Blue colour Red colour Indigo colour
10. An orbital can have maximum number of
electrons is
2 4 6 10
11. Inverse of wavelength is called Frequency Wave number Time period All of these
12. The sub shellwhich has only one orbital is
identified by the letter
s p D F
13. Electron behave like Particle Wave Both Non meterial
14. P-orbital have …….shape Spherical Dumbbell Sausage Even more
complicated
15. If n=3 then l= 0,1,2 1,2,3 _2,_3,0,1,2 -3,-2,-1,3,2,1
16. Energy of photon is inversely proportional to Frequency mass Wave number Wavelength
17. Which atomic orbital has lowest energy? 4f 5d 6p 7s

Section-Il: Short questions
2. Attempt only EIGHT questions. 8 x 2= 16
i. How the idea of the proton can be verified by taking hy-
drogen gas in the discharge tube?
ii. Why e/m value of the cathode rays is just equal to that of
electron?
iii. Why positive rays are also called canal rays?
iv. The e/m value for positive rays obtained from hydrogen
gas is 1836 times less than that of cathode rays. Justify it.
v. Why is it necessary to decrease the pressure in the dis-
charge tube to get the remains the same?
vi. How do you justify that radius of orbit in H-atom is in-
versely proportional to the number of proton in the nu-
cleus?
vii. What is the function of azimuthal quantum number?
viii.State Pauli’s exclusion principle,
ix. What is stark effect and Zeeman Effect?
x. Define spectrum. Give its two types.
xi. Differentiate between slow and fast neutrons.
xii. Describe electrons in orbital’s of 24
Cu and 29
Cr
3. Attempt only 8 questions 8 X 2 = 16
i. What is aufbau principle?
ii. What is self rotation of electron?
iii. Give the relationship between energy and frequency.
iv. Give two defects of Rutherford atomic model?
v. Why e/m value of cathode rays is the same for all gases?
vi. What is frequency and wavelength?
vii. Write de-Broglie equation .What does it show?
viii.Gases do not conduct electricity at normal pressure.
Why?
ix. What are the bases of Schrodinger wave equation?
x. Define Heisenberg principle. Give mathematical relation?
i. Define Hund’s rule and give example.
ii. What particles are formed by the decay of free neutron?
iii. Give two defects of Bohr’s model?
iv. Write balanced equation for two nuclear reaction.
v. Total energy of the bounded electron is also negative?
vi. Compare line emission and line absorption spectrum?
vii. Give the postulates of Bohr’s atomic orbital. Which pos-
tulate tells us that the orbits are stationary and energy is
quantized?
viii.What is the formula for calculating the energy of elec-
tron?
ix. What are quantum numbers give their significance.
x. Give some properties of cathode rays?
Section-lIl: Long Questions.
Attempt any THREE questions. 8 x 3 = 24
5) A) Calculate the value of principal quantum number if an
electron in hydrogen atom revolves in an orbit of energy
-0.242 x10-18
J
b) Justify that the energy difference between 2nd
and 3rd
orbits is approximately five times small-
er than that between 1st
and 2nd
orbit.
6) a ) Derivation of radius of revolving electron in nth or-
bit?
b) Measurement of charge on electron by Mil-
likan oil drop method .
7) a) Write a detailed note on production of x-rays. In-
cluding importance of Mosley’s law?
b) write electronic configuration of elements hav-
ing following atomic numbers
22, 23, 36,30,15,19.29,24,34,11,3. Also name the el-
ements having above mentioned atomic num-
bers.
8) a) Write a note on any two Quantum Numbers.
b) Rutherford’s atomic model is based on the
scattering of alpha particles from a thin gold
foil. Discuss it and explain the conculsion.
9) a) Explain the discovery of neutron and their properties.
b)What is J,J Thomson experiment for determining e/m
value of electron? And explain postulates of Bohr’s
atomic modal.

Section-l: Short questions
2. Attempt only EIGHT questions. 8 x 2= 16
i. How the idea of the proton can be verified by taking hydrogen gas in the discharge tube?
Ans: Positive Rays are produced, when high speed cathode rays (electrons) strike the molecules of a gas
enclosed in the discharge tube. They knock out electrons from the gas molecules and positive ions are
produced, which start moving towards the cathode.
M + e -
M+
+ 2e-
ii. Why e/m value of the cathode rays is just equal to that of electron?
Ans:A cathode ray consists of beam of electrons, so cathode rays are actually electrons. The e/m of cath-
ode rays is 1.7588 x 1011
C/Kg which is equal to e/m of electron. Therefore e/m value of cathode ray is
just equal to that of electron.
iii. Why positive rays are also called canal rays?
Ans: Since positive rays produced in the discharge tube passed through the canals or holes of cathode,
therefore positive rays are also called canal rays.
iv. The e/m value for positive rays obtained from hydrogen gas is 1836 times less than that of cathode
rays. Justify it.
Ans: The mass of hydrogen gas is 1836 times more than that of an electron. Cathode rays consist of beam
of electrons. The e/m value for positive rays depends upon the gas used in the tube, and e/m value for
cathode rays is independent of the nature of the gas. Therefore e/m value for positive rays obtained
from H2
gas is 1836 times less than that of cathode rays. Heavier the gas, the smaller the e/m value for
positive rays.
v. Why is it necessary to decrease the pressure in the discharge tube to get the remains the same?
Ans: The current does not flow through the gas at ordinary pressure even at high voltage about 500 volts.
However when the pressure inside the tube is decreased, the gas in the tube begins to conduct electric-
ity at low pressure. Therefore it is necessary to decrease the pressure in the discharge tube to get the
cathode rays.
vi. How do you justify that radius of orbit in H-atom is inversely proportional to the number of proton
in the nucleus?
Ans: According to radius of orbital:
In the above equation , h , and e are constantfactors and if we also fixed the orbit number ‘n’ then we
can write as
where z is number of protons in nucleus. Hence radius is inversely proportional to the number of protons
in the nucl eus.
vii. What is the function of azimuthal quantum number?

Ans: It determines the shape of orbital. It can have any integer value from 0 to n–l. This quantum number
is used to represent the sub–shells, and these value are l = 0, 1, 2, 3. These values represent different sub–
shells which are designated as s, p, d, and f, with values of l = 0, 1, 2, 3 respectively.
viii. State Pauli’s exclusion principle.
Ans: It is impossible for two electrons residing in the same orbital of a poly-electron atom to have the
same values of four quantum numbers. Or
Two electrons in the same orbitals should have opposite spins (↑↓).
ix.What is stark effect and Zeeman Effect?
Ans:
Zeeman Effect: When the excited atoms of hydrogen are placed in a magnetic field, its spectral lines are
further split up in to closely spaced lines. This type of splitting of spectral lines is called Zeeman Effect.
Stark Effect: When the excited hydrogen atom are placed in an electric field, its spectral lines are further
split up into closely spaced lines. This type of splitting of spectral lines is called stark effect.
x. Define spectrum. Give its two types.
Ans:
Spectrum: The dispersion of the components of white light, when it is passed through prism is called
spectrum. The distribution among various wavelengths of the radiant energy emitted or absorbed by an
object is also called spectrum.
Types: (A) Continuous spectrum (B) Line spectrum
xi. Differentiate between slow and fast neutrons.
Ans:
Sr # Fast Neutrons Slow neutrons
1. Those neutrons which travel with an
energy of 1.2 Mev are called as fast
neutrons.
Those neutrons which travel with
an energy of 1 ev are called slow
neutrons.
2. The fast neutrons are not used in
fission reactions because these are
absorbed by the nucleus of the atom
and simply change their path on
colliding with nucleus, therefore
they don’t cause the fission reaction
The slow neutrons are extensively
used in fission reactions because
these can easily penetrate into the
nucleus and thus cause nuclear
fission reactions.
xii. Describe electrons in orbital’s of 24
Cu and 29
Cr
Ans : 29
Cu = 1s2
, 2s2
, 2p6
, 3s2
3p6
, 3d10
, 4s1
24
Cr = 1s2
, 2s2
, 2p6
, 3s2
3p6
, 3d5
, 4s1
i. What is aufbau principle?
Ans: The electrons shall be filled in energy sub shells in order of increasing energy values. The electrons
are first placed in 1s, 2s, 2p and so on.
ii. What is self rotation of electron?
Ans: In 1925, Goudsmit and Uhledbech suggested that an electron while moving in an orbital around the
nucleus also rotates or spin about its own axis either in a clockwise or anti-clockwise direction, this is
called self rotation.
iii. Give the relationship between energy and frequency.
Ans: According to planks quantum theory, the amount of energy associated with a quantum of radiation

is proportional to the frequency (ν) of the radiation.
Mathematically
where h is planks constant and its value is 6.626 x 10-24
js
iv. Give two defects of Rutherford atomic model?
Ans:
Defects of Rutherford’s atomic model:
• In this model, behavior of electrons remained unexplained in the atom.
• Ruther ford’s planet like picture was defective and unsatisfactory because the moving electron must be
accelerated towards the nucleus. Therefore the radius of the orbiting electrons should become smaller
and smaller and the electron should fall into the nucleus. Thus an atomic structure as proposed by
Rutherford would collapse.
v. Why e/m value of cathode rays is the same for all gases?
Ans:
The e/m value of positive rays depends upon the nature of gas used in the discharge tube. The charac-
teristic of the gas varies from gas to gas, but for cathode rays e/m value is independent of the nature of
the gas. Therefore, e/m values of positive rays for different gases are different but those for cathode rays
the e/m value is the same.
vi. What is frequency and wavelength?
Ans: Frequency (V):
The number of waves passing through a point per second is called frequency (ν). Its units are cycles s–1
.
Wavelength (λ):
The distance between two successive crests or troughs is called wavelength “λ” and is expressed in Ao
or nm.
vii. Write de-Broglie equation .what does it show?
According to de Broglei, all matter particles in motion have a dual character. It means that electrons,
protons, neutrons, atoms, and molecules, possess the characteristics of both the material particle and a
wave. This is called wave particle duality in matter.
de-Broglei derived a mathematical equation which relates the wavelength (λ) of the electron to the
momentum of electron (mv)
Where
λ = wavelength
v = velocity of electron
m = mass of electron and
h = Planck’s constant.
viii. Gases do not conduct electricity at normal pressure. Why?
Ans: At low pressure, gases molecules are away from each other, that’s why gases cannot conduct cur-

rent at normal pressure.
ix. What are the bases of Schrodinger wave equation?
Ans:
according to schrodinger, although the position of an electron cannot be found exactly, the probability
of finding an electron at a certain position at any time can be found.
The solution of the wave equation gives probability of an electron at a distance r from the nucleus is
calculated for the hydrogen atom in the ground state is obtained.
x. Define Heisenberg principle. Give mathematical relation?
Ans:
Heisenberg showed that it is impossible to determine simultaneously both the position and momen-
tum of an electron. Suppose that Δx is the uncertainty in the measurement of the position and Dp is
the uncertainty in the measurement of momentum of an electron.
This relationship is called uncertainty principle.
xi. What are continuous and line spectrum?
Ans:
Continuous spectrum:
A spectrum containing light of all wavelengths is called continuous spectrum. In this type of spectrum,
the boundary line between the colours cannot be marked. The colours diffuse into each other. One co-
lour merges into another without any dark space. The best example of continuous spectrum is rainbow.
Line spectrum:
When an element or its compound is volatilized on a flame and the light emitted is seen through, a
spectrometer. We see distinct lines separated by dark spaces. This type of spectrum is called line spec-
trum. This is the characteristic of an atom.
i. Define Hund’s rule and give example .
Ans:
If, degenerate orbitals are available and more than one electrons are to be placed in them, they should
be placed in separate orbitals with the same spin rather putting them in the same orbital with opposite
spins.
According to the rule, the two electrons in 2p subshell of carbon will be distributed as follows
C = 1s,2s,2px
,2py
,2pz
The three orbitals of 2p subshell are degenerate.
ii. What particles are formed by the decay of free neutron?
iii. Give two defects of Bohr’s model?
Defects:
1. Bohr’s theory can successfully explain the origin of the origin of the spectrum of H-atom and ions
like He+1
Li+2
and Be+3
etc. These are all one electron systems. But this theory is not able to explain
the origin of the spectrum of multi-electrons or poly-electrons system like He , Li and Be etc.
2. Bohr Suggested that circular orbits of electrons around the nucleus of Hydrogen atom, but researches
have shown that the motion of electron is not in a single plane, but takes place in three dimensional

space. Actually, the atomic model is not flat.
iv. Write balanced equation for two nuclear reaction.
Ans:
v. Total energy of the bounded electron is also negative?
Ans: The total energy of bounded electron is negative because the electron is under the force of attraction
of the nucleus to have a stable state of the atom. More over when we calculate the total energy of the
bounded electron, which is the sum of K.E. and P. E comes which is also negative.
vi. Compare line emission and line absorption spectrum.
Ans.
Sr # Line emission spectrum Line absorption spectrum
1. An atomic spectrum which consists of bright
lines against a dark background is called line
emission spectrum.
An atomic spectrum which consists of bright
lines against a dark background is called line
emission spectrum.
2. When solids are volatilized or elements in their
gaseous states are heated to high temperature or
subjected to an electrical discharge, radiation of
certain wavelengths are emitted.
When a beam of white light is passed through
the gaseous sample of element, the element
absorbs certain wavelength while the rest of
wavelengths pass through it.
vii. Give the postulates of Bohr’s atomic orbital. Which postulate tells us that the orbits are station-
ary and energy is quantized?
Ans:
Electrons present in a particular orbit neither emits nor absorbed energy while moving in the same
fixed orbits. The energy is emitted or absorbed only when an electron jumps from one orbit to another.
viii. What is the formula for calculating the energy of electron?
Ans:
The energy of electron in different orbits can be calculated by using the following equation:
Energy of an electron is inversely proportional to n2
ix. What are quantum numbers give their significance.
Ans:
Quantum Numbers:
Quantum numbers are the set of numerical values which give the acceptable solutions to Schrodinger

wave equation for hydrogen atom.
Significance:
a) These numbers describe the behavior of electron in an atom completely.
b) These numbers tells us about the size, shape, spin of shell and subshell of atom.
c) Quantum tells us about the completely address of electron in an atom.
x. Give some properties of cathode rays.
Ans:
Properties of cathode rays:
• They are produced by the negative electrode, or cathode, in an evacuated tube, and travel towards the
anode.
• They travel in straight lines and cast sharp shadows.
• They have energy and can do work.
• They are deflected by electric and magnetic fields and have a negative charge
Section-ll: Long Questions. 8 x 3 = 24
5) a) Calculate the value of principal quantum number if an electron in hydrogen atom revolves in an
orbit of energy -0.242 x10-18
J.
b) Justify that the energy difference between 2nd
and 3rd
orbits is approximately five times smaller than that
between 1st
and 2nd
orbit.
6) a) Derivation of radius of revolving electron in nth
orbit?
b) Measurement of charge on electron by Millikan oil drop method.
7) a) Write a detailed note on production of x-rays including importance of Mosley’s law?
b) Write electronic configuration of elements having following atomic numbers
22, 23, 36, 30, 15, 19, 29, 24, 34, 11, 3.Also name the elements having above mentioned atomic numbers.
8) a) Write a note on any two Quantum Numbers.
b) Rutherford’s atomic model is based on the scattering of alpha particles from a thin gold foil. Discuss it
and explain the conclusion.
9) a) Explain the discovery of neutron and their properties.
b) What is J.J Thomson experiment for determining e/m value of electron? Explain postulates of Bohr’s
atomic modal.

Chapter#6:Chemical Bonding Malik Chemistry
Name : CH # Solutions Class 11th
Chemistry Test # 09, CH # 09 (Complete) Marks : 85
Section-I Objective
1. Choose the correct answer 17 x 1=17
1. A solution is defined as a Homogeneous mixture
of two or more
substances
Heterogeneous
mixture of two or more
substances
Homogeneous
mixture of
liquid or solid
components
only
Homogeneous
mixture consisting
of water as one of
the components
2. Which of the following shows negative deviation
from Roults law
CHCl3
and COCH3
Benzene and ethyl
alcohol
C6
H5
CH3
and
benzene
Benzene and
CCl4
3. An azeotropic mixture of two liquids boils at a
lower temperature than either of them when
It is saturated It shows negative
deviation from Roult
law
It does not
deviate from
Roults law
It shows positive
deviation from
Roults law
4. If 18 g of glucose is present in 1000g of solvent
,the solution is said to be
1 molar 0.5 molal 0.1 molar 0.1 molal
5. The molarity of pure water is 100M 50M 55.6M 18M
6 If 5.85 g of NaCl are dissolved in 90 g of water
,the mole fraction of solute is
0.02 0.1 0.01 0.2
7. Which is not a colligative property Osmotic pressure Depression in freezing
point
Lowering
in vapour
pressure
Refractive index
8. When a non-volatile solute is dissolved in solvent
,the relative lowering in vapour pressure is equal
to
Mole fraction of solvent Mole fraction of solute Conc. of
solute in g/L
Conc. Of solute in
g/100ml
9. The molal elevation constant is the ratio of the
elevation in boiling point to
Molarity Mole fraction of solute Molality Mole fraction of
solvent
10. Beckmann’s thermometer measures Boiling point of the
solution
Freezing point of
solution
Any
temperature
Elevation in
boiling point or
depression in
freezing point
11. The freezing point of 1 % of lead nitrate soln. in
water will be
2 o
C 1 o
C > 0o
C 0 o
C
12. Name the partially miscible liquids from the
following
Alcohol-ether Benzene-water Nicotine-
water
Both A and B
13. Osmotic pressure of a solution is …..property Obligative Fractional Colligative Automated
14. Ethanol-water is a ….mixture Azeotropic Ideal Benedict Aliphatic
15. In order to measure the molecular mass from
Roults law ,we select
A volatile solute in
solution
An electrolyte in
solution
A non-
electrolyte
and non-
volatile solute
A non-electrolyte
in concentrated
solution
16. The solution of sugar, salt and water is the
example of ….solution.
Binary Ternary Concentrated None
17. Which of the following is temperature
independent
Molar solution Molal solution Both None

i. Why the ioni zation energies decrease down the
group although the nuclear charge increase?
ii. Ionization energy increases across the period of
periodic table. Why?
iii. How M.O.T justifies that the atoms cannot
make the He2?
iv. The abnormality of bond length in HI is less
prominent than in HCl. Why?
v. What is octet rule? What is deviation of its rule?
vi. How does the electronegativity difference de-
cide the nature of chemical bond?
vii. Explain the term bond order? How can it be cal-
culated?
viii.Why ionization energy decrease within the
group and increase along a period?
ix. No bond in chemistry is 100 percent ionic .Jus-
tify?
x. Define bond energy and bond length?
xi. Pi bonds are more diffused than sigma bond
why?
xii. The abnormalities of CO2
and CS2
are zero but
that of SO2
is 1.61D. Justify
3. Attempt only 8 questions 8x2=16
i. Sigma bond is stronger than pie bond .why?
ii. Anionic radius is always larger than parent
atom. Why?
iii. Why the energy of bonding molecular orbits is
lower than that of antibonding molecular orbit-
als?
iv. What is coordinate covalent bond? Give exam-
ples.
v. What is dipole moment? Give its mathematical
form.
vi. Why the atomic radii increases down the group
and decrease along the period of periodic table?
vii. Why there is difference in the energy levels of
O2
and N2
with 2px
, 2Py
and 2Pz
?
viii.Differentiate between bonding molecular orbit-
als and antibonding molecular orbitals.
ix. Group VlllA elements show abnormal values of
electronegativity in every period .justify?
x. Why HF is weaker acid than HCl?
xi. Bond distance is the compromise distance be-
tween two atoms. Give reason.
4. Attempt any 6 questions 6 x 2= 12
i. Why atomic radius cannot determine precisely?
ii. Define electronegativity? Give its trend along
periodic table.
iii. Why the 2nd
electron affinity of oxygen is posi-
tive?
iv. How the percentage ionic character of polar
bond can be determined?
v. Why the molecule of BF3
is triangular planar?
vi. Give the sequence of molecular orbitals in ni-
trogen molecule?
vii. Give the basic postulates of M.O.T
viii.What is hybridization? What are degenerate or
bitals?
ix. Why some gases are inert?
Section-Ill: Long Questions.
Attempt any THREE questions. 8 x 3 = 24
5) a) give postulates of VSEPR theory ans also give
two suitable examples
b) Write a detailed note on dipole moment with ex-
amples
6) a) Draw molecular orbital structure of nitrogen
and oxygen?
b) Write a detailed note on energetic of bond for-
mation?
7) a) Describe bonding and draw structure of
methane ,ammonia ,water, boron triflouride
and ethyne
b) Write the effects of the type of bond on physical
and chemical properties of compounds and also
describe which type of information is provided
by dipole moment?
8) a) Explain atomic orbital hybridization with ref-
erence to sp3
, sp2
and sp modes of hybridization
of PH3
, C2
H4
and C2
H2
.
b) Write note on electronegativity and write briefly
trend in periodic table.
9) a) What do you know about ionization energy?
Give its periodic trend in detail.
b) Write comprehensive note on coordinate cova-
lent bond.

i. Why the ionization energies decrease down the group although the nuclear charge increases?
Ans: it is due to
a) Increase atomic size
b) Increasing shell number
c) Increases the distance between nucleus and valance electron
d) Decreasing nuclear forces attraction on valance electrons
So due to increasing atomic size, removing valance electrons from valance shell is easy. That’s why ioniza-
tion energy is decreased down the group although nuclear charge increases.
ii. Ionization energy increases across the period of periodic table. Why?
Ans: it is due to:
a) Constant shell number
b) Decreasing atomic size
c) Decreasing distance between nucleus and valance electron
d) Increasing nuclear forces of attraction on valance electron
Each period begins with an element which has one electron in its valance shell and ends with comple-
tion of an electronic shell.
The increase in the atomic number is associated with the increase in nuclear charge which leads to a
stronger force of attraction between the nucleus and the increasing number of electrons.
The stronger force of attraction, ultimately results in difficult to removal of electrons.
iii. How M.O.T justifies that the atoms cannot make the He2?
iv. The abnormality of bond length in HI is less prominent than in HCl. Why?
Ans:
Chlorine has higher electronegative than iodine. So, the polarities of HCI and HI bonds are unequal.
HCl (127 pm) bond lenght is smaller than HI (161 pm). Therefore, abnormality of bond length and
bond strength of HCI is more prominent than HI.
v. What is octet rule? What is deviation of its rule?
Ans:
Octet Rule:
The tendency of the atoms to attain a maximum of eight electrons in the valence shell is called octet
rule.
Deviation of octet rule:
PF5
, SF6
and BCl3
are those molecules which don’t follow octet rule.
vi. How does the electronegativity difference decide the nature of chemical bond?
Ans:

• When the electronegativity difference between two bonded atoms is 1.7 or more than that, then the
bond is said to be ionic.
• When electronegativity difference between two bonded atoms is lower than 1.7 then bond is said to be
covalent.
• The % age of ionic character is more the 50 % when the electro negativity difference is 1.7.
vii. Explain the term bond order? How can it be calculated?
Ans: Bond Order:
The bond order is half the difference between the number of bonding electrons and the number of
antibonding electrons.
viii. Why electron affinity decrease within the group and increase along a period?
Ans: Periodic Trend:
In group: it is due to
a) Increase atomic size
b) Increasing shell number
c) Increases the distance between nucleus and valance electron
d) Decreasing nuclear forces attraction on valance electrons
So due to increasing atomic size, removing valance electrons from valance shell is easy. That’s why ion-
ization energy is decreased down the group although nuclear charge increases.
In Period: it is due to:
a) Constant shell number
b) Decreasing atomic size
c) Increase nuclear charge
d) Decreasing distance between nucleus and valance electron
e) Increasing nuclear forces of attraction on valance electron
Each period begins with an element which has one electron in its valance shell and ends with comple-
tion of an electronic shell.
ix. No bond in chemistry is 100 percent ionic .justify?
Ans:
• Criteria of electronegativity also help us to understand the nature of bond. So, in order to decide the
% of ionic nature in a compound, it is better to note the difference of electronegativity between the
bonded atoms. If the difference is 1.7 or more then the bond is said to ionic.
• Ionic character depends upon electronegativity. If two elements form molecule and one has zero elec-
tronegativity then compound will be 100 % ionic character. You should know that no atom in this
universe has zero electronegativity. Least electronegative atom in periodic table is Cs = 0.7 and highest
is F = 4.0 and bond will be 92 % ionic in CsF. Therefore, its impossible 100 % ionic character bond in
chemistry.
x. Define bond energy and bond length?
Ans:
Bond length:
The distance between the nuclei of two atoms forming a covalent bond is called bond length. In general
it is the sum of the covalent radii of the combined atoms.
Bond energy:

The bond energy is defined as the average amount of energy required to break all bonds of particular
type in one mole of substance. It is determined by measuring the heat involved in a chemical reaction.
It is also defined as the energy required to break Avogadro’s number (6.02 x 1023
) of bonds or the energy
released when an Avogadro number of bonds are formed. It is a measure of strength of bonds. The bond
energy is measured in KJ mol–1
.
xi. pi bonds are more diffused than sigma bond. Why?
In sigma bond electrons are attracted between two nuclei with strongly due to more effective
head to head overlapping. In pi bond, electrons are not strongly attracted between nuclei due to weak
parallel overlapping. So pi electrons and orbital spread a wide area.
xii. The abnormalities of CO2
and CS2
are zero but that of SO2
is 1.61D. Justify
structures where the dipoles being equal and opposite. Then they cancel out each other’s effect.
i. Sigma bond is stronger than pi bond. Why?
Ans: In a σ bond, the electrons are in orbitals between the nuclei of the bonding atoms. Electron density
is greatest between the nuclei. The electrons attract the nuclei and form a σ bond — the strongest type
of covalent bond.
In a π bond, the p orbitals overlap side wahy to sideway .The overlap is less efficient, because the elec-
tron density is off to the sides of the σ bond.The electrons are not as effective in attracting the two
nuclei. Thus, a π bond is weaker than a σ bond.
ii. Anionic radius is always larger than parent atom. Why?
Ans: Anion is formed by the gaining of electron of parent atom. The number of protons remain same in
the anion as parent atom and thus nuclear forces of attraction for the valance electrons reduces. The
distance between nucleus and valance electrons increases. That’s why anion is larger than parent atom.
Example:
Atomic radius of F = 64 pm
Anionic radius of F-
= 136 pm
iii. Why the energy of bonding molecular orbits is lower than that of anti-bonding molecular orbit-
als?
Ans:
In chemical bonding theory, an antibonding orbital is a type of molecular orbital (MO) that, if occu-
pied by electrons, weakens the bond between two atoms and helps to raise the energy of the molecule
relative to the separated atoms. Such an orbital has one or more nodes in the bonding region between

the nuclei.
The density of the electrons in the orbital is concentrated outside the bonding region and acts to pull
one nucleus away from the other and tends to cause mutual repulsion between the two atoms.
iv. What is coordinate covalent bond? Give examples.
Ans: Coordinate covalent bond:
A coordinate covalent bond is for a bond formed when both electrons of the bond are denoted by one
atom.
Examples:
H3
O+
, PH4
+
, HNO3
, HClO4
, HClO3
, HClO2
and NH3
-BF3
complex are best examples of coordinate co-
valent bond.
NH4
+
is an example of coordinate covalent bond.
v. What is dipole moment giving its mathematical form?
Ans: Dipole moment:
The dipole moment may be defined as the product of electric charge (q) and distance (r) between the
two oppositely charged centres.
Mathematical form: It is represented by μ which is equal to
μ= q x r
It is vector quantity as it has magnitude and direction. It plays a major role in determining the % age
ionic character of a covalent bond and the shapes of molecules.
vi. Why the atomic radii increases down the group and decrease along the period of periodic table?
Ans: Along group:
It is increased due to increasing shell number, decreasing nuclear forces of attraction on valance
electron, increasing shielding affect. Therefore distance between nucleus and valance electrons is
increased.
Along period:
It is decreased due to constant shell number but increasing protons and electrons, increasing nuclear
forces of attraction on valance electrons, constant shielding effect. Therefore, distance between nucleus
and valance electrons is decreased
vii. Why there is difference in the energy levels of O2
and N2
with 2px
, 2Py
and 2Pz
?
• Its due to the energy difference between Nitrogen and Oxygen orbitals

F.sc. Part 1 Chemistry Chapterwise Test Solved by Malik Xufyan

F.sc. Part 1 Chemistry Chapterwise Test Solved by Malik Xufyan

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