Solution MCQ Set-1

Question 1

An aqueous solution of hydrochloric acid

Accepted Answer

Shows negative deviation from Raoult’s law

Answer

Obeys Raoult’s law

Answer

Shows positive deviation from Raoult’s law

Answer

Obeys Henry’s law at all compositions

Question 2

Exactly $1\ g$ of urea dissolved in $75\ g$ of water gives a solution that boils at $100.114^\circ C$ at 760 torr. The molecular weight of urea is 60.1. The boiling point elevation constant for water is

Accepted Answer

0.51

Answer

1.02

Answer

3.06

Answer

1.51

Question 3

$12\ g$ of urea is dissolved in 1 litre of water and $68.4\ g$ of sucrose is dissolved in 1 litre of water. The lowering of vapour pressure of first case is

Accepted Answer

equal to second

Answer

greater than second

Answer

less than second

Answer

double that of second

Question 4

At a particular temperature, the vapour pressures of two liquids A and B are respectively 120 and 180 mm of mercury. If 2 moles of A and 3 moles of B are mixed to form an ideal solution, the vapour pressure of the solution at the same temperature will be (in mm of mercury)

Accepted Answer

156

Answer

145

Answer

150

Answer

108

Question 5

The freezing point of equimolal aqueous solution will be highest for

Accepted Answer

$C_6H_{12}O_6$

Answer

$C_6H_5NH_3^+Cl^–$

Answer

$Ca(NO_3)_2$

Answer

$La(NO_3)_2$

Question 6

Which of the following $0.10\ m$ aqueous solutions will have the lowest freezing point ?

Accepted Answer

$Al_2(SO_4)_3$

Answer

$C_6H_{12}O_6$

Answer

$KCl$

Answer

$C_{12}H_{22}O_{11}$

Question 7

A solution containing $10\ g$ per $dm^3$ of urea (molecular mass = $60\ g\ mol^{–1}$) is isotonic with a $5\%$ solution of a non volatile solute. The molecular mass of this non volatile solute is

Accepted Answer

$300\ g\ mol^{–1}$

Answer

$350\ g\ mol^{–1}$

Answer

$200\ g\ mol^{–1}$

Answer

$250\ g\ mol^{–1}$

Question 8

The vapour pressure of a solvent decreases by $10\ mm\ of\ Hg$ when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent if the decrease in the vapour pressure is to be $20\ mm\ of\ Hg$ ?

Accepted Answer

0.6

Answer

0.8

Answer

0.4

Answer

0.2

Question 9

A solution containing $1.8\ g$ of a compound (empirical formula $CH_2O$) in $40\ g$ of water is observed to freeze at $–0.465^\circ C$. The molecular formula of the compound is ($K_f$ of water = $1.86\ kg\ K\ mol^{–1}$)

Accepted Answer

$C_6H_{12}O_6$

Answer

$C_2H_4O_2$

Answer

$C_3H_6O_3$

Answer

$C_4H_8O_4$

Question 10

Which observation(s) reflect(s) colligative properties?
(i) A $0.5\ m\ NaBr$ solution has a higher vapour pressure than a $0.5\ m\ BaCl_2$ solution at the same temperature
(ii) Pure water freezes at the higher temperature than pure methanol
(iii) a $0.1\ m\ NaOH$ solution freezes at a lower temperature than pure water

Accepted Answer

(i) and (iii)

Answer

(i), (ii) and (iii)

Answer

(i) and (ii)

Answer

(ii) and (iii)

Question 11

The vapour pressure of benzene at $30^\circ C$ is $121.8\ mm$. By adding $15\ g$ of non-volatile solute in $250\ g$ of benzene, its vapour pressure is decreased to $120.2\ mm$. The molecular weight of solute is :

Accepted Answer

$356.3\ g$

Answer

$156.6\ g$

Answer

$267.4\ g$

Answer

$467.4\ g$

Question 12

Pure benzene freezes at $5.45^\circ C$. A $0.374\ m$ solution of tetrachloroethane in benzene freezes at $3.55^\circ C$. The $K_f$ for benzene is:

Accepted Answer

5.08

Answer

0.508

Answer

50.8

Answer

508

Question 13

$0.450\ g$ of urea (mol.wt.60) in $22.5\ g$ of water show $0.170^\circ C$ of elevation in boiling point. The molal elevation constant of water is:

Accepted Answer

$0.51^\circ C$

Answer

$0.051^\circ C$

Answer

$5.1^\circ C$

Answer

$0.83^\circ C$

Question 14

The colligative property is not represented by :

Accepted Answer

optical activity

Answer

elevation in boiling point

Answer

osmotic pressure

Answer

relative lowering of vapour pressure

Question 15

$20\ g$ of a substance were dissolved in $500\ mL$ of water and the osmotic pressure of the solution was found to be $600\ mm$ of mercury at $15^\circ C$. The molecular weight of substance is :

Accepted Answer

1198

Answer

998

Answer

1028

Answer

1098

Question 16

Which one of the statements given below concerning properties of solutions, describes a colligative effect?

Accepted Answer

Vapour pressure of pure benzene decreases by the addition of naphthalene

Answer

Boiling point of pure water decreases by the addition of ethanol

Answer

Vapour pressure of pure water decreases by the addition of nitric acid

Answer

Boiling point of pure benzene increases by the addition of toluene

Question 17

The average osmotic pressure of human blood is $7.8\ bar$ at $37^\circ C$. What is the concentration of an aqueous NaCl solution that could be used in the blood stream?

Accepted Answer

$0.31\ mol / L$

Answer

$0.16\ mol/L$

Answer

$0.60\ mol / L$

Answer

$0.45\ mol / L$

Question 18

A $5\%$ solution (by mass) of cane sugar in water has freezing point of $271\ K$ and freezing point of pure water is $273.15\ K$. The freezing point of a $5\%$ solution (by mass) of glucose in water is

Accepted Answer

$269.07\ K$

Answer

$271\ K$

Answer

$273.15\ K$

Answer

$277.23\ K$

Question 19

The vapour pressure of pure benzene at a certain temperature is $0.850\ bar$. A non-volatile, nonelectrolyte solid weighing $0.5\ g$ is added to $39.0\ g$ of benzene (molar mass $78\ g/mol$). The vapour pressure of the solution then is $0.845\ bar$. What is the molecular mass of the solid substance?

Accepted Answer

170

Answer

58

Answer

180

Answer

145

Question 20

$0.01\ M$ solution of $KCl$ and $BaCl_2$ are prepared in water. The freezing point of $KCl$ is found to be $–2^\circ C$. What is the freezing point of $BaCl_2$ to be completely ionised ?

Accepted Answer

$– 3^\circ C$

Answer

$+ 3^\circ C$

Answer

$– 2^\circ C$

Answer

$– 4^\circ C$

Question 21

“The importance of many pure substance in life depends on their composition.” Which of the following statement justify the above fact?

Accepted Answer

All of the above.

Answer

$1\ ppm$ of fluoride ions in water prevents tooth decay.

Answer

$1.5\ ppm$ of fluoride ions causes tooth decay.

Answer

Concentration above $1.5\ ppm$ can be poisonous.

Question 22

Which of the following fluoride is used as rat poison?

Accepted Answer

$NaF$

Answer

$CaF_2$

Answer

$KF$

Answer

$MgF_2$

Question 23

Most of the processes in our body occur in

Accepted Answer

liquid solution

Answer

solid solution

Answer

gaseous solution

Answer

colloidal solution

Question 24

The term homogenous mixtures signifies that

Accepted Answer

both composition and properties are uniform throughout the mixture.

Answer

its composition is uniform throughout the mixture.

Answer

its properties are uniform throughout the mixture.

Answer

neither composition nor properties are uniform throughout the mixture.

Question 25

Which of the following mixture is(are) called solution?
(i) water + ammonia
(ii) water + acetone
(iii) acetone + alcohol
(iv) hexane + water

Accepted Answer

(i), (ii) and (iii)

Answer

(i), (iii) and (iv)

Answer

(i) and (iv)

Answer

(ii) and (iii)

Question 26

Which of the following is a quantitative description of the solution?

Accepted Answer

Molar

Answer

Dilute

Answer

Concentrated

Answer

Saturated

Question 27

When a solute is present in trace quantities the following expression is used

Accepted Answer

Parts per million

Answer

Gram per million

Answer

Milligram percent

Answer

Microgram percent

Question 28

Molarity of liquid $HCl$ will be, if density of solution is $1.17\ gm/cc$

Accepted Answer

32.05

Answer

36.5

Answer

18.25

Answer

42.10

Question 29

$1\ M, 2.5\ litre\ NaOH$ solution is mixed with another $0.5\ M, 3\ litre\ NaOH$ solution. Then find out the molarity of resultant solution

Accepted Answer

$0.73\ M$

Answer

$0.80\ M$

Answer

$1.0\ M$

Answer

$0.50\ M$

Question 30

An $X$ molal solution of a compound in benzene has mole fraction of solute equal to $0.2$. The value of $X$ is

Accepted Answer

3.2

Answer

14

Answer

1.4

Answer

2

Question 31

The molarity of the solution containing $7.1\ g$ of $Na_2SO_4$ in $100\ ml$ of aqueous solution is

Accepted Answer

$0.5\ M$

Answer

$2\ M$

Answer

$1\ M$

Answer

$0.05\ M$

Question 32

The vapour pressure of pure benzene at $25^\circ C$ is $640\ mm\ Hg$ and that of solution of solute A is $630\ mm\ Hg$. The molality of solution is

Accepted Answer

$0.2\ m$

Answer

$0.4\ m$

Answer

$0.5\ m$

Answer

$0.1\ m$

Question 33

$4.0\ g$ of $NaOH$ is dissolved in $100\ ml$ solution. The normality of the solution is

Accepted Answer

$1.0\ N$

Answer

$0.1\ N$

Answer

$0.5\ N$

Answer

$4.0\ N$

Question 34

The molarity of pure water is

Accepted Answer

$55.6\ M$

Answer

$50\ M$

Answer

$18\ M$

Answer

$100\ M$

Question 35

An aqueous solution of glucose is $10\%$ in strength. The volume in which $1\ g$ mole of it is dissolved, will be

Accepted Answer

$1.8\ litre$

Answer

$9\ litre$

Answer

$8\ litre$

Answer

$0.9\ litre$

Question 36

$10\ g$ of $NaCl$ is dissolved in $10^6\ g$ of the solution. Its concentration is

Accepted Answer

$10\ ppm$

Answer

$100\ ppm$

Answer

$0.1\ ppm$

Answer

$1\ ppm$

Question 37

On adding a solute to a solvent having vapour pressure $0.80\ atm$, vapour pressure reduces to $0.60\ atm$. Mole fraction of solute is

Accepted Answer

0.25

Answer

0.75

Answer

0.50

Answer

0.33

Question 38

$2.5\ litres$ of $NaCl$ solution contain $5\ moles$ of the solute. What is the molarity?

Accepted Answer

2 molar

Answer

5 molar

Answer

2.5 molar

Answer

12.5 molar

Question 39

The mole fraction of the solute in one molal aqueous solution is

Accepted Answer

0.018

Answer

0.009

Answer

0.027

Answer

0.036

Question 40

$5\ ml$ of $N\ HCl$, $20\ ml$ of $N/2\ H_2SO_4$ and $30\ ml$ of $N/3\ HNO_3$ are mixed together and volume made to one litre. The normality of the resulting solution is

Accepted Answer

$N/40$

Answer

$N/5$

Answer

$N/20$

Question 41

$25\ ml$ of a solution of barium hydroxide on titration with a $0.1$ molar solution of hydrochloric acid gave a titre value of $35\ ml$. The molarity of barium hydroxide solution was

Accepted Answer

0.07

Answer

0.14

Answer

0.28

Answer

0.35

Question 42

Mole fraction of the solute in a $1.00\ molal$ aqueous solution is

Accepted Answer

0.0177

Answer

0.1770

Answer

0.0344

Answer

1.7700

Question 43

What is the normality of a $1\ M$ solution of $H_3PO_4$?

Accepted Answer

$3.0\ N$

Answer

$0.5\ N$

Answer

$1.0\ N$

Answer

$2.0\ N$

Question 44

The volume of $4\ N\ HCl$ and $10\ N\ HCl$ required to make 1 litre of $6\ N\ HCl$ are

Accepted Answer

$0.67\ litre$ of $4\ N\ HCl$ and $0.33\ litre$ of $10\ N\ HCl$

Answer

$0.75\ litre$ of $10\ N\ HCl$ and $0.25\ litre$ of $4\ N\ HCl$

Answer

$0.50\ litre$ of $4\ N\ HCl$ and $0.50\ litre$ of $10\ N\ HCl$

Answer

$0.80\ litre$ of $4\ N\ HCl$ and $0.20\ litre$ of $10\ N\ HCl$

Question 45

Molarity of $H_2SO_4$ is $18\ M$. Its density is $1.8\ g/ml$. Hence molality is

Accepted Answer

500

Answer

36

Answer

200

Answer

18

Question 46

$200\ ml$ of water is added to $500\ ml$ of $0.2\ M$ solution. What is the molarity of this diluted solution ?

Accepted Answer

$0.1428\ M$

Answer

$0.5010\ M$

Answer

$0.2897\ M$

Answer

$0.7093\ M$

Question 47

How many grams of concentrated nitric acid solution should be used to prepare $250\ mL$ of $2.0\ M\ HNO_3$? The concentrated acid is $70\%\ HNO_3$

Accepted Answer

$45.0\ g$ conc. $HNO_3$

Answer

$90.0\ g$ conc. $HNO_3$

Answer

$70.0\ g$ conc. $HNO_3$

Answer

$54.0\ g$ conc. $HNO_3$

Question 48

For preparing $0.1\ N$ solution of a compound from its impure sample of which the percentage purity is known, the weight of the substance required will be

Accepted Answer

More than the theoretical weight

Answer

Less than the theoretical weight

Answer

Same as the theoretical weight

Answer

None of these

Question 49

If $N/10\ 50\ ml\ H_2SO_4$, $N/3\ 30\ ml\ HNO_3$, $N/2\ 10\ ml\ HCl$ is mixed and solution is made to $1\ L$. Then normality of resultant solution is

Accepted Answer

$N/40$

Answer

$N/20$

Answer

$50/N$

Answer

$N$

Question 50

A solution made by dissolving $40\ g\ NaOH$ in $1000\ g$ of water is

Accepted Answer

1 molal

Answer

1 molar

Answer

1 normal

Answer

None of these

Question 51

Which of the following concentration terms is/are independent of temperature?

Accepted Answer

Molality and mole fraction

Answer

Molality only

Answer

Molarity and mole fraction

Answer

Molality and normality

Question 52

A solution is prepared by dissolving $10\ g\ NaOH$ in $1250\ mL$ of a solvent of density $0.8\ mL/g$. The molality of the solution in $mol\ kg^{–1}$ is

Accepted Answer

0.25

Answer

0.2

Answer

0.008

Answer

0.0064

Question 53

Which of the following units is useful in relating concentration of solution with its vapour pressure?

Accepted Answer

mole fraction

Answer

parts per million

Answer

mass percentage

Answer

molality

Question 54

Which of the following concentration unit is independent of temperature ?

Accepted Answer

Molality

Answer

Normality

Answer

Molarity

Answer

Formality

Question 55

Which of the following factor do not affect solubility of solid solute in liquid ?

Accepted Answer

Pressure

Answer

Temperature

Answer

Nature of solute

Answer

All of these

Question 56

When a solid solute is added to the solvent, some solute dissolves and its concentration increases in solution. This process is known as ______. Some solute particles in solution collide with the solid solute particles and get separated out of solution. This process is known as ______.

Accepted Answer

Dissolution, crystallization.

Answer

Crystallization, dissolution.

Answer

Dissolution, saturation.

Answer

Saturation, crystallization.

Question 57

At the state of dynamic equilibrium, for solute + solvent $\rightleftharpoons$ solution.

Accepted Answer

Rate of dissolution = Rate of unsaturation.

Answer

Rate of dissolution = Rate of saturation

Answer

Rate of crystallization = Rate of saturation.

Question 58

Which of the following statements is incorrect?

Accepted Answer

The minimum amount of solute dissolved in a given amount of solvent is its solubility.

Answer

A solution in which no more solute can be dissolved at the same temperature and pressure is called a saturated solution.

Answer

An unsaturated solution is one in which more solute can be dissolved at the same temperature.

Answer

The solution which is in dynamic equilibrium with undissolved solute is the saturated solution.

Question 59

On dissolving sugar in water at room temperature solution feels cool to touch. Under which of the following cases dissolution of sugar will be most rapid ?

Accepted Answer

Powdered sugar in hot water.

Answer

Sugar crystals in cold water.

Answer

Sugar crystals in hot water.

Answer

Powdered sugar in cold water.

Question 60

The solubility of a solid in a liquid is significantly affected by temperature changes. Solute + Solvent $\rightleftharpoons$ Solution. The system being in a dynamic equilibrium must follow Le-chatelier’s principle. Considering the Le-chatelier’s principle which of the following is correct?

Accepted Answer

$	riangle H_{sol} < 0$; solubility $\downarrow$ ; temperature $\uparrow$

Answer

$	riangle H_{sol} > 0$; solubility $\uparrow$ ; temperature $\downarrow$

Answer

$	riangle H_{sol} > 0$; solubility $\downarrow$ ; temperature $\uparrow$

Questions in this Quiz

More Quizzes for Class 12

Solution MCQ Set-1

Questions in this Quiz

More Quizzes for Class 12

Chemistry

Mathematics

Physics