1. 6.
7.
8.
Calculate the molarity of 9.8% (w/W) solution of
H,SO, if the density of the solution is 1.02 g mL1.
(Molar mass of H,SO, =98g mol)
(2/5, Foreign2014) (Ev
Differentiate between molarity and molality ofa
solution. How can we change molality value of a
solution into molarity value? (Delhi 2014C) (An
SAII (3 marks)
A
solution of glucose (molar mass = 180gmol) in
water is labelled as 10% (by mass). What would be
the molality and molarity of the solution?
(Density ofsolution =1.2 gmL-)
(NCERT,3/5, Al2014)
2. 12. Why aquatic animals are more comfortable in cold
water than in warm water? (1/3, 2018) (Ap
13. Gas (A)is more soluble in water than gas (B) at the
same temperature. Which one of the two gases will
have the higher value of Ku (Henry's constant) and
why?
(1/2, Al 2016)
3. 17. State Henry's law and mention two of its important
applications.
18. Give reasons for the following.
(2020 C) (U
(a) Aquatic species are more comfortable in cold
water than inwarm water.
(b) At higher altitudes people suffer from anoxia
resulting ininability tothink. (AI2019) (Ap
4. 26. (a) Differentiate between ldeal solution and Non
idealsolution.
(b) 30 g of urea is dissolved in 846 gof water.
Calculate the vapour pressure of water for this
solution if vapour pressure of pure water at
298 Kis 23.8 mm Hg. (2023)
5. 31. What is meant by positive deviations from Raoult's
law? Give aneXample. What isthe sign of AmiH for
positive deviation?
OR
(Delhi2015)
What is meant by negative deviation from Raoult's
law? Give anexample. What is the sign of AmiHfor
negative deviation? (Foreign 2015)
6. 45. (a) State Henry's law and mention its two
applications.
(b) 5% aqueous solution of a non-volatile solute
was made and its vapour pressure at 373 K
was found to be 745 mm. Vapour pressure of:
pure water at this temperature was 760mm.
Calculate the molar mass of solute.
(2020C) Ap
7. 52. Calculate the freezing point of asolution containing
60gofglucose (molar masS =180g mol)in250gof
water. (K, ofwater =1.86 Kkg mol) (2018)
53. Calculate the mass of compound (molar mass - 256 g
mol-)to be dissolved in 75 g of benzene to lower its
freezing point by 0.48 K. (K,= 5.12 Kkg mol
(Delhi2014)
8. 54. An antifreeze solution is prepared by dissolving31 g
of ethylene glycol (Molar mass =62 gmol) in 600 g
of water.Calculate the freezing point of the solution.
(K,for water =1.86Kkg mol) (2020)
55. Calculate the mass of ascorbic acid (Molar mass =
176g mo-) to be dissolved in 75 gof acetic acid, to
lower itsfreezing point by 1.5°C.
(K=3.9 Kkg mol-) (NCERT Intext, 2020)
9. 58. A 5% solution (by mass) of cane-sugar in water has
freezing point of 271 K. Calculate the freezing point
of 5% solution(by mass)of glucose in water if the
freezing point of purewater is 273.15 K.
[Molecular masses:Glucose CaH,0;: 180 amu;
Cane-sugar C1HO11:342amu]
(NCERT, 3/5,Delhi2019C) Ev
10. 65. What happens when a
pressure greater than osmotic
pressure is applied on the solution side separated
from solvent by asemi-permeable membrane?
(1/2, 2020) (Ap
66. Give reason for thefollowing:
Measurement of osmotic pressure method is
preferred for the determination of molar masses of
macromolecules such as proteinsand polymers.
(1/2, 2018)(U)
11. 69. For a 5% solution of urea(Molar mass = 60g/mol),
calculate the osmotic
[R= 0.0821 Latm K-' mol1]
70. Give reasons:
pr
pressure at 300 K.
(2020)
(a) Cooking is faster in pressure cooker than in
cooking pan.
(b) Red Blood Cells (RBC)shrink when placed in
saline water but swell in distilled water. (2019)
12. 74. Asolution containing 15 g urea (molar mass =
60g mol)perlitre of solutionin water has the same
osmotic pressure (isotonic) as a solution of glucose
(molar mass = 180g mol)in water. Calculate the
mass ofglucose present inone litre of its solution.
(3/5, Al 2014)
13. 83. Calculate the boiling point elevation for a solution
preparedby adding 10 g of CaCl, to 200 g of water.
(K, for water =
0.52 Kkg mol,molar mass of CaCl,
=111g mol-) (3/5, Al2017C, Foreign 2014)
84. Calculate the boiling point of solution when 4 g
of MgSO, (M = 120 g mol) was dissolved in 100
g
gof water, assuming MgsO4 undergoes complete
ionization.
(K, forwater =0.52 Kkg mol) (AI2016)
14. 88. When 19.5 g of F-CH,-COOH (molar mass =
78gmol )isdissolved in 500g of water,thedepression
in freezing point is observed to be 1°C. Calculate the
degree of dissociation of F-CH,-COOH.
[Given: K
forwater =1.86 Kkg mol-] (3/5, 2020) (Ev
89. The freezing point of a solution containing 5 g of
benzoic acid (M= 122g mol-)in 35g of benzene
is depressed by 2.94 K. What is the percentage
association of benzoic acid if it forms a dimer in
solution? (K,for benzene =4.9 Kkg mol) (2020) (An
15. 90. A
0.01 m aqueous solution of AlCI, freezes at
-0.068 °C. Calculate the percentage of dissociation.
[Given: kK,forwater =1.86 Kkg mol] (2020) Ev)
91. Calculate the freezing point ofsolution when1.9 gof
MgCl, (M=95g mol)
was dissolved in 50g of water,
assuming MgCl, undergoes complete ionization.
(K,forwater - 1.86 Kkg mol-1) (Delhi 2016)
16. 94. Calculate the mass of NaCI (molar mass = 58.5
gmol) to be dissolved in 37.2g ofwater to lowerthe
freezing point by 2°C, assuming that NaClundergoes
completedissociation. (K,forwater=1.86 Kkg mol)
(Foreign2015)
17. 98. A
solution O.1 Mof Na,SO,is dissolved to the extent
of 95%. What would be its osmotic pressure at 27°C?
(R= 0.0821 Latm K-' mol-) (2019)
