Questions
Download PDF
Free download in PDF CBSE Class 12 Chemistry Multiple Choice Questions(MCQs) & Answers. Here Gkseries provide Chemistry Solve Questions and Answers for CBSE Class 12 Students.
1
The molal elevation constant depends upon
A
nature of the solvent.
B
enthalpy change.
C
vapour pressure of the solution.
D
nature of solute.
View Answer
Answer: nature of the solvent.
2
The van’t Hoff factor (i) accounts for
A
degree of solubilisation of solute.
B
the extent of dissociation of solute.
C
the extent of dissolution of solute.
D
the degree of decomposition of solution.
View Answer
Answer: the extent of dissociation of solute.
Advertisement
3
People add sodium chloride to water while boiling eggs. This is to
A
increase the boiling point.
B
prevent the breaking of eggs.
C
decrease the boiling point.
D
make eggs tasty.
View Answer
Answer: increase the boiling point.
4
Osmotic pressure of a solution is 0.0821 atm at a temperature of 300 K. The concentration in moles/litre will be
A
0.33
B
0.666
C
0.3 × 10-2
D
None
View Answer
5
Which has the lowest boiling point at 1 atm pressure?
A
0.1 M Urea
B
0.1 M A1Cl3
C
0.1 M KCl
D
0.1 M CaCl2
View Answer
6
The boiling point of an azeotropic mixture of water and ethanol is less than that of water and ethanol. The mixture shows
A
no deviation from Raoult’s Law.
B
positive deviation from Raoult’s Law.
C
negative deviation from Raoult’s Law.
D
that the solution is unsaturated.
View Answer
Answer: positive deviation from Raoult’s Law.
7
Out of molality (m), molarity (M), formality (F) and mole fraction (x), those which are independent of temperature are
A
m, x
B
M, x
C
M, m
D
F, x
View Answer
8
Mole fraction of glycerine C3H5(OH)3 in solution containing 36 g of water and 46 g of glycerine is
A
0.40
B
0.46
C
0.36
D
0.20
View Answer
9
In the following question a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
A
Assertion and reason both are correct statements and reason is correct explanation for assertion.
B
Assertion and reason both are incorrect statements.
C
Assertion and reason both are correct statements but reason is not correct explanation for assertion.
D
Assertion is correct statement but reason is wrong statement.
View Answer
Answer: Assertion and reason both are incorrect statements.
10
Relative lowering of vapour pressure is a colligative property because ________ .
A
It depends on the concentration of a non electrolyte solute in solution and does not depend on the nature of the solute molecules.
B
It depends on the concentration of an electrolyte or nonelectrolyte solute in solution as well as on the nature of solute molecules.
C
It depends on the concentration of a non electrolyte solute in solution as well as on the nature of the solute molecules.
D
It depends on number of particles of electrolyte solute in solution and does not depend on the nature of the solute particles.
View Answer
Answer: It depends on the concentration of a non electrolyte solute in solution and does not depend on the nature of the solute molecules.
11
Benzoic acid, when dissolved in benzene, which of the following is correct.
A
The benzoic acid will undergo dissociation.
B
The benzoic acid will undergo association.
C
Observed molar mass of benzoic acid in benzene will less than normal molar mass.
D
Observed molar mass of benzoic acid in benzene is more than normal molar mass.
View Answer
Answer: The benzoic acid will undergo association.
12
Which has the highest freezing point?
A
1 M glucose
B
1 M AlF3
C
1 M NaCl
D
1 M CaCl2
View Answer
13
The temperature at which 10% aqueous solution of (W/V) of glucose will show the osmotic pressure of 16.4 atom is (R = 0.082 L atom K-1 mol-1)
A
360 K
B
300 K
C
180 K
D
360°C
View Answer
14
If molality of dilute solution is doubled, the value of molal depression constant (Kf) will be
A
halved
B
tripled
C
unchanged
D
doubled
View Answer
15
At 100°C, the vapour pressure of a solution of 6.5 g of solute in 100 g of water is 732 mm. If Kb is 0.52 K/m, the boiling point of solution will be [HOTS]
A
102°C
B
103°C
C
101 °C
D
100°C
View Answer
16
When 1 mole of benzene is mixed with 1 mole of toluene (vapour pressure of benzene – 12.8 kPa, Toluene = 3.85 kPa)
A
The vapour will contain equal amount of benzene and toluene.
B
Not enough information is given for prediction.
C
The vapour will contain a higher percentage of benzene.
D
The vapour will contain higher percentage of toluene.
View Answer
Answer: The vapour will contain a higher percentage of benzene.
17
What is mole fraction of solute in 1.00 m aqueous solution?
A
0.0354
B
0.0177
C
1.770
D
0.177
View Answer
18
Cone. H2SO4 is 98 % H2SO4 by mass has d = 1.84 g cm-3. Volume of acid required to make one litre of 0.1 M H2SO4 is
A
30 mL
B
5.55 mL
C
10 mL
D
20 mL
View Answer
19
A solution containing 10 g per dm3 of urea (molar mass 60 g mol-1) is isotonic with 5% solution of non-volatile solute, MB of solute is
A
250 g mol-1
B
300 g mol-1
C
350 g mol-1
D
200 g mol-1
View Answer
20
The value of Henry’s constant KH is _________ .
A
greater for gases with higher solubility.
B
greater for gases with lower solubility.
C
constant for all gases.
D
not related to the solubility of gases.
View Answer
Answer: greater for gases with lower solubility.