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CHEMISTRY – REVISION SHEET
XII : CBSE
SOLUTION
Subjective Type Questions
Each Question carries 1 Mark
1.
Explain the Henry‟s law about dissolution of a gas in a liquid.
2.
State Raoult‟s law for a solution of volatile liquids.
3.
What is meant by molality of the solution?
4.
State the main advantage of molality over molarity as the unit of concentration.
5.
Define mole fraction.
6.
Differentiate between molarity and molality of a solution.
7.
Two liquids A and B boil at 145°C and 190°C. Which of them has a higher vapour pressure at 80°C?
8.
Why is vapour pressure of a solution of glucose in water lower than that of pure water?
9.
State Raoult‟s law for solution of non-volatile solutes.
10.
Define ideal solution.
11.
Define the term azeotropes.
12.
Define the term osmotic pressure.
13.
State the condition resulting in reverse osmosis.
14.
What are isotonic solutions?
15.
Measurement of which colligative property is preferred for determination of molar mass of biomolecules?
16.
What is meant by colligative properties?
17.
Define the term Van‟t Hoff factor.
18.
What is meant by reverse osmosis?
19.
Some liquids on mixing form “Azeotropes”. What are azeotropes?
20.
Explain boiling point elevation constant for a solvent.
Each Question carries 2 Marks —
21.
A 6.90 M solution of KOH in water contains 30% by mass of KOH. Calculate the density of KOH solution.
[Given : Molar mass of KOH = 56 g mol-1]
22.
If the density of water of a lake is 1.25 g mL-1 and 1 kg of lake water contains 92 g of Na + ions, calculate the
molality of Na + ions in this lake water. [Given : Gram atomic mass of Na = 23 g mol-1]
23.
State Henry‟s law correlating the pressure of a gas and its solubility in a solvent and mention two
applications for the law.
24.
Henry‟s law constant (K H) for the solution of methane in benzene at 298 K is 4.27  105 mm Hg. Calculate
the solubility of methane in benzene at 298 K under 760 mm Hg.
25.
A solution of glucose (C6H12O6) in water is labelled as 10% by weight. What would be the molality of
solution? (Molar mass of glucose = 180 g mol-1)
26.
Calculate the molarity of 9.8% (w/W) solution of H2SO4 if the density of the solution is 1.02 g mL-1. (Molar
mass of H2SO4 = 98 g mol-1)
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27.
Urea forms an ideal solution with water. Determine the vapour pressure of an aqueous solution containing
10% by mass of urea at 40°C. (Vapour pressure of water at 40°C = 55.3 mm Hg)
28.
The vapour pressure of water is 12.4 kPa at 300 K. Calculate the vapour pressure of a one molal solution of
a non-volatile, non-ionic solute in water.
29.
Explain why a solution of chloroform and acetone shows negative deviation from Raoult‟s law?
30.
State how the vapour pressure of a solvent is affected when a non-volatile solute is dissolved in it.
31.
Calculate the temperature at which the solution containing 54 g of glucose, C6H12O6 in 250 g of water will
freeze. (Kf for water = 1.86 K kg mol-1)
32.
Define term osmotic pressure. Describe how the molecular mass of substance can be determined by a
method based on measurement of osmotic pressure.
33.
Calculate the freezing point of a solution containing 0.520 g glucose (C 6H12O6) dissolved in 80.20 g of
water. (For water Kf = 1.86 K kg mol-1)
34.
Calculate the freezing point depression expected for 0.0711 m aqueous solution of Na 2SO4. If this solution
actually freezes at -0.320°C, what would be the value of Van‟t Hoff factor? (Kf for water = 1.86°C mol-1)
35.
A 0.2% aqueous solution of a non-volatile solute exerts vapour pressure of 1.004 bar at 100°C. What is the
molar mass of the solute?
36.
A 4% solution of sucrose is isotonic with 3% solution of an unknown organic substance. Calculate the
molecular mass of unknown substance.
37.
What is the mole fraction of a solute, in 2.5 m aqueous solution?
Each Question carries 3 Marks
38.
Henry‟s law constant for CO2 dissolving in water is 1.67  108 Pa at 298 K. Calculate the quantity of CO2
in. 1 L of soda water when packed under 2.5 atm CO2 pressure at 298 K.
39.
Calculate the molarity and molality of a 15% solution (by weight) of sulphuric acid of density 1.020 g cm-3.
(Given : Atomic masses of H = 1, O = 16, S = 32 u)
40.
An antifreeze solution is prepared from 222.6 g of ethylene glycol C 2H4(OH)2 and 200 g of water. Calculate
the molality of the solution. If the density of this solution is 1.072 g mL -1, then what will be the molarity of
the solution?
41.
The solubility of pure nitrogen gas at 25°C and 1 atm is 6.8  10-4 mol L-1. What is the concentration of
nitrogen dissolved in water under atmospheric conditions? The partial pressure of nitrogen gas in the
atmosphere is 0.78 atm.
42.
At 300 K, 36 g of glucose, C6H12O6 is dissolved in one litre solution which has an osmotic pressure of 4.98
bar. If the osmotic pressure of another glucose solution is 1.52 bar at the same temperature, calculate the
concentration of. the other solution.
43.
Calculate the temperature at which a solution containing 54 g of glucose, (C6H12O6) in 250 g of water will
freeze. (Kf for water = 1.86 K kg mol-1 and molar mass of glucose = 180 g mol-1)
44.
A solution containing 8 g of a substance in 100 g of diethyl ether boils at 36.86°C, whereas pure ether boils
at 35.60°C. Determine the molecular mass of the solute. [For ether, K b = 2.02 K kg mol-1]
45.
The freezing point of a solution containing 0.2 g acetic acid in 20.0 g of benzene is lowered by 0.45°C.
Calculate (i) the molar mass of acetic acid from this data (ii) van‟t Hoff factor. [For benzene, K f = 5.12 K
kg mol-1] What conclusion can you draw from the value of van‟t Hoff factor obtained?
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46.
The boiling point elevation of 0.30 g acetic acid in 100 g benzene is 0.0633 K. Calculate the molar mass of
acetic acid from this data. What conclusion can you draw about the molecular state of the solute in the
solution?
47.
Calculate the mass of a non-volatile solute (molar mass 40 g mol-1), which should be dissolved in 114 g of
octane to reduce its vapour pressure to 80%. (Given : Molar mass of octane = 114 g mol-1]
48.
A 5% solution (by mass) of cane sugar in water has a freezing point of 271 K. Calculate the freezing point
of 5% (by mass) solution of glucose in water. The freezing point of pure, water is 273.15 K. (Molar mass of
cane sugar = 342 g mol-1 and molar mass of glucose = 180 g mol-1)
49.
100 mg of a protein is dissolved in just enough water to make 10.0 mL of solution. If this solution has an
osmotic pressure of 13.3 mm Hg at 25°C, what is the molar mass of the protein? R = 0.0821 L atm mol-1 K-1
and 760 mm Hg = 1 atm.
50.
Calculate the amount of sodium chloride which must be added to one kilogram of water so that the freezing
point of water is depressed by 3 K. [Given : K f = 1.86 K kg mol-1, atomic mass of Na = 23 u, Cl = 35.5 u]
51.
A solution of urea in water has a boiling point of 373.128 K. Calculate the freezing point of the same
solution. [Given : for water K f = 1.86 km-1 and Kb = 0.52 km-1]
52.
Calculate the freezing point depression expected for 0.0711 m aqueous solution of Na2SO4. If this solution
actually freezes at -0.320°C, what would be the value of van‟t Hoff factor? (Given : Kf for water is 1.86°C
mol-1)
Each Question carries 5 Marks
53.
(a)
A 0.2 percent aqueous solution of a nonvolatile solute exerts a vapour pressure of 1.004 bar at 100°C.
What is the molar mass of the solute? (Given: Vapour pressure of pure water at 100°C is 1.013 bar
and molar mass of water is 18 g mol-1.)
(b)
Calculate the freezing point of a solution containing 18 g glucose, C 6H12O6 and 68.4 g sucrose,
C12H22O6 in 200 g of water. The freezing point of pure water is 273 K and Kf for water is 1.86 km-1.
54.
(a)
Find the freeing point of a solution containing 0.520 g glucose (C6H12O6) dissolved in 80.2 g of water
[Given : Kf for water = 1.86 Km-1]
(b)
A solution of glycerol (C3H8O3) in water was prepared by dissolving some glycerol in 500 g of water.
This solution has a boiling point of 100.42°C, what mass of glycerol was dissolved to make this
solution? (Kb for water = 0.512 K kg mol-1)
55.
(а)
Define the term osmotic pressure. Describe how the molecular mass of a substance can be determined
by a method based on measurement of osmotic pressure?
(b)
0.1 mole of acetic acid was dissolved in 1 kg of benzene. Depression in freezing point of benzene was
determined to be 0.256 K. What conclusion can you draw about the state of the solute in solution?
[Given : Kf for benzene = 5.12 Km-1]
56.
(a)
The depression in freezing point of water observed for the same molar concentrations of acetic acid,
trichloroacetic acid and trifluoroacetic acid increases in the order as stated above. Explain.
(b)
What mass of NaCl must be dissolved in 65.0 g of water to lower the freezing point of water by
7.50°C? The freezing point depression constant (K f) for water is 1.86°C/m. Assuming van‟t Hoff
factor for. NaCl is 1.87. (Molar mass of NaCl = 58.5 g mol-1)
57.
(a)
Find the boiling point of a solution containing 0.520 g of glucose dissolved in 80.2 g of water.
[Given : Kb for water = 0.52 Km-1]
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(b)
What mass of ethylene glycol (molar mass 62.0 g mol-1) must be added to 5.50 kg of water to lower
the freezing point of water from 0°C to - 10.0°C? (Kf for water = 1.86 K kg mol-1)
PREVIOUS YEAR BOARD QUESTIONS + HOTS
58.
Show that when the mole fraction of the solvent in the solution is nearly unity, the molarity (C) and
molality (m) of the solution are connected by the equation.
59.
Match the following if the molecular weight of X, Y and Z are the same :
Solvent
X
Y
Boiling point
100°C
27oC
Kb
0.68
0.53
60.
Z
253°C
0.98
What type of mixtures of two liquids distil over at one temperature and why?
61.
Why a person suffering from high blood pressure is advised to take minimum quantity of common salt?
62.
Why melting point of a substance is used as a criterion for testing the purity of the substance?
Value Based Questions
63.
On a week end, Rahul went on a picnic with his parents. There was a beautiful view of a lake but suddenly,
Rahul saw some fish floating on the surface of water of the lake as they had died. Rahul asked his parents
why these fish had died. They told him that fish also need oxygen for their survival as we do. Dissolved
oxygen in the water gets depleted due to discharge of human sewage and organic wastes of the industries
into the lake water.
After reading the above paragraph, answer the following questions:
64.
(a)
What lesson do you learn from the explanation given by Rahul‟s parents to him?
(b)
How dissolved oxygen gets depleted due to presence of the organic waste?
Amit went to a meat shop to buy meat from the butcher. While buying the meat, he observed that the
butcher was highly upset. When he asked him the reason, he told that he was suffering a heavy loss as his
meat gets spoiled very soon. Amit suggested him that he should apply common salt on the meat to save it
from spoilage.
After reading the above passage, answer the following questions :
65.
(a)
What values are expressed by Amit?
(b)
Why did Amit suggest him to apply salt on the meat? How does it work?
There was a medical check-up of teeth of a particular class in a school. It was found that some students had
cavities in their teeth. The teacher asked them two questions. First, how many chocolates or sweets do they
eat? Second, which toothpaste do they use for brushing their teeth, i.e., does it contain fluoride or not?
After reading the above paragraph, answer the following questions :
(a)
What values are expressed by the teacher?
(b)
What is the limiting value of the fluoride that should be present in the toothpaste? What happens if
this limit is exceeded?
(c)
66.
How does fluoride protect our teeth?
A deep sea diver was facing problems while diving deep into the water though he was carrying air tank
along with him. He was feeling discomfort and pain in breathing while ascending. He consulted a doctor
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and doctor advised him to take diluted air in the tank (11.7% He, 56.2% nitrogen and 32.1% oxygen). By
doing so, his problem solved and he no longer felt this again.
67.
(a)
Why was deep sea diver facing discomfort while breathing?
(b)
Name the medical condition developed by the use of air.
(c)
How did doctor help him?
(d)
What is the value associated with the advice given by the doctor?
Rakesh is suffering from high blood pressure. His grandson Pankaj a student of class XII Chemistry
advised him to take minimum quantity of common salt in his diet and takes him for regular morning walk.
68.
(a)
What is the role of common salt (NaCl) in increasing blood pressure?
(b)
How does less intake of NaCl help in reducing the blood pressure?
(c)
Mention the values exhibited by Pankaj.
Rachit was a habitual late comer to school. His class teacher discussed and found that his mother was
cooking the traditional way in open vessels to prepare lunch for her family in the morning. Teacher
suggested his mother to purchase a pressure cooker that can be used for cooking.
69.
(a)
Why did the teacher suggest Rachit‟s mother to purchase a pressure cooker?
(b)
What values are associated with the teacher‟s suggestion?
Nisha‟s grandmother lives in Shimla. In winter, there is lot of snow in front of the house. She asked Nisha
to clear the snow from the road infront of the house. Nisha added sodium chloride to clear snow.
70.
(a)
How salt causes melting of ice and clears the road?
(b)
Mention the values associated with this act of Nisha.
Neha is a housewife, she purchased 2 L cold drink bottle. Due to their big size, Neha prefer not to keep
them in her refrigerator. She generally opens the bottle, pour the cold drink, add ice and serve. She finds
that the cold drink which was fizzy at the time of opening, hardly has any fizz by the time the bottle is
finished after 3-4 days. Her son Atul a student of class XII chemistry suggested that she Should thoroughly
chill the bottle before opening it and then to keep the same in refrigerator, tightly capped, till it is fully
consumed.
(a)
How Atul‟s suggestion help Neha in this matter?
(b)
Name the law involved in the explanation of Atul‟s suggestion.
(c)
Mention the values associated with Atul‟s suggestion.
Each Question carries 1 Mark
71.
Give an examples of „liquid in solid‟ type solution.
72.
Which type of solid solution will result by mixing two solid components with large difference in the sizes
of their molecules?
73.
What is meant by semimolar and decimolar solutions?
74.
What will be the mole fraction of water in C 2H5OH solution containing equal number of moles of water and
C2H5OH?
75.
Which method is adopted for expressing the concentration of a solution, when the number of components in
solution are more than two?
76.
Which of the following is a dimensionless quantity; molarity, molality or mole fraction?
77.
10 gm glucose is dissolved in 400 gm. of solution. Calculate percentage concentration of the solution.
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78.
Gases tend to be less soluble in liquids as the temperature is raised. Why?
79.
State the conditions which must be satisfied if an ideal solution is to be formed.
80.
A mixture of chlorobenzene and bromobenzene forms nearly ideal solution but a mixture of chloroform and
acetone does not. Why?
81.
How is the concentration of a solute present in trace amount in a solution expressed?
82.
Which aqueous solution has higher concentration 1 molar or 1 molal solution of the same solute?
Given reason.
83.
N2 and O2 gases have KH values 76.48 Kbar and 34.86 kbar respectively at 293 K temperature. Which of
these will have more solubility in water?
84.
Under what condition molality and molarity are identical. Explain with suitable reason.
85.
Addition of Hgl2 to Kl (aq.) shows decrease in vapour pressure. Why?
86.
What will happen to the boiling point of the solution on mixing two miscible liquids showing negative
deviation from Raoult‟s law.
87.
Liquid 'Y' has higher Vapour pressure than liquid „X‟, which of them will have higher boiling point?
88.
When 50 mL of ethanol and 50 mL of water are mixed, predict whether the volume of the solution is equal
to, greater than or less than 100 mL. Justify.
89.
Which type of deviation is shown by the solution formed by mixing cyclohexane and ethanol?
90.
A and B liquids on mixing produce a warm solution. Which type of deviation from Raoult‟s law is there?
91.
Define cryoscopic constant.
92.
Mention the unit of ebulioscopic constant.
93.
If kf for water is 1.86 K kg mol-1. What is the freezing point of 0.1 molal solution?
94.
Name the component that separate first when salt solution is frozen.
95.
What is reverse osmosis? Give one large scale use of it.
96.
What is the value of Van‟t Hoff factor (i) for Na 2SO4 . 10H2O?
97.
What colligative property should be measured for (i) thermally unstable compound (ii) compound having
very low solubility at room temperature.
98.
What is the value of Van‟t Hoff factor (i) if solute molecules undergo dimerisation.
99.
Under what conditions is Van‟t Hoff factor less than one?
100.
The Phase diagram for pure solvent and the solution containing non-volatile solute are recorded below. The
quantity indicated by „X‟ in the figure is
101.
AgNOg on reaction with NaCl in aqueous solution gives white precipitate. If the two solutions are
separated by a semi-permeable membrane will there be appearance of a white ppt. in the side „X‟ due to
osmosis?
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Each Question carries 2 Marks
102.
103.
Explain the following :
(a)
Solubility of a solid in a liquid involves dynamic equilibrium.
(b)
Ionic compounds are soluble in water but are insoluble in non-polar solvents.
Give two examples each of a solution :
(a)
showing positive deviation
(b)
showing negative deviation
104.
Some non-ideal solutions show positive deviations while some other negative deviations. Why?
105.
Draw Vapour pressure vs composition (in terms of mole fraction) diagram for an ideal solution.
106.
Define azeotropes. Mention their important characteristics.
107.
Draw the total vapour pressure Vs. mol fraction diagram for a binary solution exhibiting non-ideal
behaviour with negative deviation.
108.
The vapour pressure curve for three solutions having the same non-volatile solute in the same solvent are
shown. The curves are parallel to each other and do not intersect. What is the correct order of the
concentrations of the solutions.
109.
Describe the following by giving a suitable example in each case :
(a)
minimum boiling azeotropes
(b)
maximum boiling azetropes
110.
Show that the relative lowering of vapour pressure of a solvent is a colligative property.
111.
Benzene and toluene form a nearly ideal solution. At a certain temperature, calculate the vapour pressure of
solution containing equal moles of the two substances.
[Given : P°Benzene = 150 mm of Hg, P°Toluene = 55 mm of Hg]
112.
What is meant by abnormal molecular mass? Illustrate it with suitable examples.
113.
When 1 mole of NaCl is added to 1 litre water the boiling point increases. When 1 mole of CH3OH is added
to 1 litre water, the boiling point decreases. Suggest reason.
114.
Can we separate water completely from HNO3 solution. Justify your answer.
115.
1 gram each of two solutes „A‟ and ,„B‟ (molar mass of A > molar mass of B) are dissolved separately in
100 gram each of the same solvent. Which solute will show greater elevation in boiling point. Why?
Each Question carries 3 Marks
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116.
Define molarity and molality. List two main points of difference between molarity and molality of a
solution.
117.
(a)
State and explain Henry‟s Law.
(b)
If O2 is bubbled through water at 393 K how many millimoles of O2 gas would be dissolved in 1L of
water? Assume that O2 exerts a pressure of 0.95 bar.
(Given KH for O2 = 46.82 bar at 393K).
118.
119.
Given reason for the following
(a) Aquatic species are more comfortable in cold water than in warm water.
(b)
To avoid bends scuba divers use air diluted with helium.
(c)
Cold drinks bottles are sealed under high pressure.
Why should a solution of a non volatile solute boil at a higher temperature? Explain with the help of a
diagram. Derive the relationship between molar mass and elevation in boiling point.
120.
121.
Account for the following
(a)
CaCl2 is used to clear snow from roads in hill stations.
(b)
Ethylene glycol is used as antifreeze solution in radiators of vehicles in cold countries.
(c)
The freezing point depression of 0.01 m NaCl is nearly twice that of 0.01 m glucose solution.
Why do colligative properties of solution of a given concentration are found to give abnormal molecular
weight of solute. Explain with the help of suitable examples.
122.
Give reasons for the following:(a)
RBC swell up and finally burst when placed in 0.1% NaCl solution.
(b)
When fruits and vegetables that have been dried are placed in water, they slowly swell and return to
original form.
123.
(c) A person suffering from high blood pressure is advised to take less amount of table salt.
Glycerine, Ethylene Glycol and methanol sell at the same price per Kg. Which would be cheaper for
preparing an antifreeze solution for the radiator of an automobile?
124.
Determine the correct order of the property mentioned against them :
(a)
10% glucose (p1) 10% urea (p2), 10% sucrose (p3)
(b)
0.1 m NaCl, 0.1 m urea, 0.1 m MgCl2
(c)
0.1 m CaCl2, 0.1 m sucrose, 0.1 m NaCl
Each Question carries 3 Marks
125.
(a)
What are ideal solutions? Give two examples.
(b)
Calculate the osmoic pressure in pasals exerted by a solution prepared by dissolving 1.0g of polymer
of mol. mass 185000 in 450 ml of water at 37°C.
126.
(a)
Describe a method of determining molar mass of a non-volatile solute from vapour pressure
lowering.
(b)
How much urea (mol. mass 60 g mol-1) must be dissolved in 50 g of water so that the vapour pressure
at the room temperature is reduced by 25%? Also calculate the molality of the solution obtained.
127.
(a)
Why is the freezing point depression considered as a colligative property?
(b)
The cryoscopic constant of water is 1.86 Km-1. Comment on this statement.
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(c)
Calculate the amount of ice that will separate out on cooling solution containing 50 g of ethylene
glycol in 200 g H2O to -9.3°C. (K, for water = 1.86 K kg mol-1)
128.
(a)
(b)
Define osmotic pressure. Explain how molecular mass of a solute can be determined by osmotic
pressure.
Why osmotic pressure is preferred over other colligative properties for the determination of
molecular mass of macromolecules?
(c)
What is the molar concentration of particles in human blood if the osmotic pressure is 7.2 atm. at
normal body temperature of 37°C?
NUMERICAL PROBLEMS
129.
Calculate the mass percentage of benzene (C 6H6) and carbon tetrachloride (CCl4), If 22 g of benzene is
dissolved in 122g of carbon tetrachloride.
130.
Calculate the molarity of a solution prepared by mixing 500 ml of 2.5 M urea solution and 500 mL of 2M
urea solution.
131.
The mole fraction of CH 3OH in an aqueous solution is 0.02 and density of solution 0.994 g cm-3. Determine
the molality and molarity.
132.
200 mL of calcium chloride solution contains 3.011  1022 Cl- ions. Calculate the molarity of the solution.
Assume that calcium chloride is completely ionized.
133.
134.
6  10-3 g oxygen is dissolved per kg of sea water. Calculate the ppm of oxygen in sea water.
The solubility of oxygen in water is 1.35  10-3 mol L-1 at 20°C and 1 atm pressure. Calculate the
concentration of oxygen at 20°C and 0.2 atm. pressure.
135.
Two liquids X and Y on mixing from an ideal solution. The vapour pressure of the solution containing 2
mol of X and 1 mol of Y is 550 mm Hg. But when 4 mol of X and 1 mole of Y are mixed, the vapour
pressure of solution thus formed is 560 mm Hg. What will be the vapour pressure of pure X and pure Y at
this temperature?
136.
An aqueous solution containing 3.12 g of barium chloride in 250 g of water is found to be boil at
100.0832°C. Calculate the degree of dissociation of barium chloride.
[Given molar mass BaCl2 = 208 g mol-1, Kb for water = 0.52 K/m]
137.
The degree of dissociation of Ca(NO3)2 in a dilute aqueous solution, containing 7.0 g of salt per 100 g of
water at 100°C is 70%. If the vapour pressure of water at 100°C is 760 mm, calculate the vapour pressure of
the solution.
138.
2g of C6H5 COOH dissolved in 25g of benzene shows depression in freezing point equal to 1.62K.
Molar freezing point depression constant for benzene is 4.9 K kg mol-1. What is the percentage association
of acid if it forms a dimer in solution?
139.
Calculate the amount of NaCl which must added to one kg of water so that the freezing point is depressed
by 3K. Given Kf = 1.86 K kg mol-1, Atomic mass : Na = 23, Cl = 35.5).
140.
Three molecules of a solute, A associate in benzene to form species A3. Calculate the freezing point of 0.25
molal solution. The degree of association of solute A is found to be 0.8. The freezing point of benzene is
5.5°C and its Kf value is 5.13 Km-1.
141.
A 5% solution of sucrose C12H22O11. is isotonic with 0.877% solution of urea. Calculate the molecular mass
of urea.
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142.
Osmotic pressure of a 0.0103 molar solution of an electrolyte was found to be 0.75 atm at 27°C. Calculate
Van‟t Hoff factor.
143.
The maximum allowable level of nitrates in drinking water as set by U.S. is 45 mg nitrate ions/dm 3. Express
this level in ppm?
144.
75.2 g of Phenol (C6H5OH) is dissolved in 1 kg solvent of Kf = 14 Km-1, if the depression in freezing point
is 7 K, then find the % of Phenol that dimerises.
145.
An aqueous solution of glucose boils at 100.01°C. The molal boiling point elevation constant for water is
0.5 K kg mol-1. What is the number of glucose molecule in the solution containing 100 g of water.
146.
A bottle of commercial H 2SO4 [density = 1.787 g/mL] is labelled as 86% by mass.
(a)
What is the molarity of the acid?
(b)
What volume of the acid has to be used to make 1 litre 0.2 M H2SO4?
(c)
What is the molality of the acid?
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