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Explore popular questions from Solutions for NEET. This collection covers Solutions previous year NEET questions hand picked by popular teachers.


Q 1.    

Correct4

Incorrect-1

If molality of the dilute solution is doubled, the value of molal depression constant {tex} \left( K _ { \rho } \right) {/tex} will be

A

halved

B

tripled

unchanged

D

doubled

Explanation

Q 2.    

Correct4

Incorrect-1

Which of the following is dependent on temperature?

Molarity

B

Mole fraction

C

Weight percentage

D

Molality

Explanation

Q 3.    

Correct4

Incorrect-1

The van't Hoff factor {tex} ( i ) {/tex} for a dilute aqueous solution of the strong electrolyte barium hydroxide is

A

0

B

1

C

2

3

Explanation



Q 4.    

Correct4

Incorrect-1

Which one of the following is incorrect for ideal solution?

A

{tex} \Delta H _ { \operatorname { mix } } = 0 {/tex}

B

{tex} \Delta U _ { \operatorname { mix } } = 0 {/tex}

C

{tex} \Delta P = P _ { \text {obs } } - P _ { \text {calculated by Raorit's law } } = 0 {/tex}

{tex} \Delta G _ { \operatorname { mix } } = 0 {/tex}

Explanation



Q 5.    

Correct4

Incorrect-1

Which of the following statements about the composition of the vapour over an ideal {tex} 1 : 1 {/tex} molar mixture of benzene and toluene is correct? Assume that the temperature is constant at {tex} 25 ^ { \circ } \mathrm { C } {/tex} . (Given, vapour pressure data at {tex} 25 ^ { \circ } \mathrm { C } , {/tex} benzene {tex} = 12.8 \mathrm { kPa } {/tex} , toluene {tex} = 3.85 \mathrm { kPa } {/tex} )

A

The vapour will contain equal amounts of benzene and toluene.

B

Not enough information is given to make a prediction.

The vapour will contain a higher percentage of benzene.

D

The vapour will contain a higher
percentage of toluene.

Explanation



Q 6.    

Correct4

Incorrect-1

At {tex} 100 ^ { \circ } \mathrm { C } {/tex} the vapour pressure of a solution of {tex}6.5 \,\mathrm { g } {/tex} of a solute in {tex}100\, \mathrm { g } {/tex} water is {tex}732\, \mathrm { mm } {/tex} . If {tex}K _ { b } = 0.52 , {/tex} the boiling point of this solution will be

A

{tex} 102 ^ { \circ } \mathrm { C } {/tex}

B

{tex} 103 ^ { \circ } \mathrm { C } {/tex}

{tex} 101 ^ { \circ } \mathrm { C } {/tex}

D

{tex} 100 ^ { \circ } \mathrm { C } {/tex}

Explanation

Q 7.    

Correct4

Incorrect-1

What is the mole fraction of the solute in a {tex} 1.00 \,\mathrm { m } {/tex} aqueous solution?

A

1.77

B

0.0354

0.0177

D

0.177

Explanation



Q 8.    

Correct4

Incorrect-1

The boiling point of {tex}0.2\, \mathrm { mol } \mathrm { kg } ^ { - 1 } {/tex} solution of {tex} X {/tex} in water is greater than equimolal solution of {tex} Y {/tex} in water. Which one of the following statements is true in this case?

A

Molecular mass of {tex} X {/tex} is less than the molecular mass of {tex} Y {/tex} .

B

{tex} Y {/tex} is undergoing dissociation in water while {tex} X {/tex} undergoes no change.

{tex} X {/tex} is undergoing dissociation in water.

D

Molecular mass of {tex} X {/tex} is greater than the
molecular mass of {tex} Y {/tex}

Explanation



Q 9.    

Correct4

Incorrect-1

Which one of the following electrolytes has the same value of van't Hoff factor {tex} ( i ) {/tex} as that of {tex} \mathrm { Al } _ { 2 } \left( \mathrm { SO } _ { 4 } \right) _ { 3 } {/tex} (if all are 100{tex} \% {/tex} ionised)?

A

{tex} \mathrm { Al } \left( \mathrm { NO } _ { 3 } \right) _ { 3 } {/tex}

{tex} \mathrm { K } _ { 4 } \left[ \mathrm { Fe } ( \mathrm { CN } ) _ { 6 } \right] {/tex}

C

{tex} \mathrm { K } _ { 2 } \mathrm { SO } _ { 4 } {/tex}

D

{tex} \mathrm { K } _ { 3 } \left[ \mathrm { Fe } ( \mathrm { CN } ) _ { 6 } \right] {/tex}

Explanation



Q 10.    

Correct4

Incorrect-1

Which of them is not equal to zero for an ideal solution?

A

{tex} \Delta V _ { \operatorname { mix } } {/tex}

B

C

{tex} \Delta H _ { \mathrm { min } } {/tex}

{tex} \Delta S _ { mix } {/tex}

Explanation



Q 11.    

Correct4

Incorrect-1

Of the following {tex} 0.10\,\mathrm { m } {/tex} aqueous solutions, which one will exhibit the largest freezing point depression?

A

{tex} \mathrm { KCl } {/tex}

B

{tex} \mathrm { C } _ { 6 } \mathrm { H } _ { 12 } \mathrm { O } _ { 6 } {/tex}

{tex} \mathrm { Al } _ { 2 } \left( \mathrm { SO } _ { 4 } \right) _ { 3 } {/tex}

D

{tex} \mathrm { K } _ { 2 } \mathrm { SO } _ { 4 } {/tex}

Explanation



Q 12.    

Correct4

Incorrect-1

How many grams of concentrated nitric acid solution should be used to prepare {tex} 250\,\mathrm { mL } {/tex} of {tex} 2.0\,\mathrm { M }\,\, \mathrm { HNO } _ { 3 } ? {/tex} The concentrated acid is {tex} 70\% \mathrm { HNO } _ { 3 } {/tex}

A

70.0{tex} \mathrm { g } {/tex} conc. {tex} \mathrm { HNO } _ { 3 } {/tex}

B

{tex} 54.0\,\mathrm { g } {/tex} conc. HNO {tex} _ { 3 } {/tex}

45.0{tex} \mathrm { g } {/tex} conc. {tex} \mathrm { HNO } _ { 3 } {/tex}

D

90.0{tex} \mathrm { g } {/tex} conc. HNO {tex} _ { 3 } {/tex}

Explanation



Q 13.    

Correct4

Incorrect-1

Which condition is not satisfied by an ideal solution?

A

{tex} \Delta _ { \operatorname { mix } } V = 0 {/tex}

{tex} \Delta _ { \operatorname { mix } } S = 0 {/tex}

C

Obeyance to Raoult's Law

D

{tex} \Delta _ { \operatorname { mix } } H = 0 {/tex}

Explanation



Q 14.    

Correct4

Incorrect-1

{tex} p _ { A } {/tex} and {tex} p _ { B } {/tex} are the vapour pressure of pure liquid components, {tex} A {/tex} and {tex} B , {/tex} respectively of an ideal binary solution. If {tex} x _ { A } {/tex} represents the mole fraction of component {tex} A , {/tex} the total pressure of the solution will be

A

{tex} p _ { A } + x _ { A } \left( p _ { B } - p _ { A } \right) {/tex}

B

{tex} p _ { A } + x _ { A } \left( p _ { A } - p _ { B } \right) {/tex}

C

{tex} p _ { B } + x _ { A } \left( p _ { B } - p _ { A } \right) {/tex}

{tex} p _ { B } + x _ { A } \left( p _ { A } - p _ { B } \right) {/tex}

Explanation



Q 15.    

Correct4

Incorrect-1

Vapour pressure of chloroform {tex} \left( \mathrm { CHCl } _ { 3 } \right) {/tex} and dichloromethane {tex} \left( \mathrm { CH } _ { 2 } \mathrm { Cl } _ { 2 } \right) {/tex} at {tex} 25 ^ { \circ } \mathrm { C } {/tex} are {tex} \mathrm 200\,{ mm } {/tex} Hg and 41.5{tex} \mathrm { mm } {/tex} Hg respectively. Vapour pressure of the solution obtained by mixing 25.5{tex} \mathrm { g } {/tex} of {tex} \mathrm { CHCl } _ { 3 } {/tex} and 40{tex} \mathrm { g } {/tex} of {tex} \mathrm { CH } _ { 2 } \mathrm { Cl } _ { 2 } {/tex} at the same temperature will be (Molecular mass of {tex} \mathrm { CH } \mathrm { Cl } _ { 3 } = 119.5 \mathrm { u } {/tex} and {tex} \left. \text { molecular mass of } \mathrm { CH } _ { 2 } \mathrm { Cl } _ { 2 } = 85 \mathrm { u } \right) {/tex}

A

{tex} 173.9\,\mathrm { mm } \mathrm { Hg } {/tex}

{tex}90.63\, \mathrm { mm } \mathrm { Hg } {/tex}

C

{tex}347.9\, \mathrm { mm } \mathrm { Hg } {/tex}

D

{tex}285.5\, \mathrm { mm } \mathrm { Hg } {/tex}

Explanation


Q 16.    

Correct4

Incorrect-1

The freezing point depression constant for water is {tex} - 1.86 ^ { \circ } \mathrm { C } \mathrm { m } ^ { - 1 } {/tex} . If {tex}5.00\, \mathrm { g }\, \mathrm { Na } _ { 2 } \mathrm { SO } _ { 4 } {/tex} is dissolved in 45.0{tex} \mathrm { g } \mathrm { H } _ { 2 } \mathrm { O } {/tex} , the freezing point is changed by {tex} - 3.82 ^ { \circ } \mathrm { C } {/tex} . Calculate the van't Hoff factor for {tex} \mathrm { Na } _ { 2 } \mathrm { SO } _ { 4 } {/tex} .

A

2.05

2.63

C

3.11

D

0.381

Explanation



Q 17.    

Correct4

Incorrect-1

The van't Hoff factor {tex} i {/tex} for a compound which undergoes dissociation in one solvent and association in other solvent is respectively

A

less than one and greater than one

B

less than one and less than one

greater than one and less than one

D

greater than one and greater than one.

Explanation



Q 18.    

Correct4

Incorrect-1

A 0.1 molal aqueous solution of a weak acid is 30{tex} \% {/tex} ionized. If {tex} K _ { f } {/tex} for water is {tex} 1.8 ^ { 6 } \mathrm { C } / \mathrm { m } , {/tex} the freezing point of the solution will be

A

{tex} - 0.18 ^ { \circ } \mathrm { C } {/tex}

B

{tex} - 0.54 ^ { \circ } \mathrm { C } {/tex}

C

{tex} - 0.36 ^ { \circ } \mathrm { C } {/tex}

{tex} - 0.24 ^ { \circ } \mathrm { C } {/tex}

Explanation



Q 19.    

Correct4

Incorrect-1

{tex}200\, \mathrm { mL } {/tex} of an aqueous solution of a protein contains its {tex}1.26\, \mathrm { g } {/tex} . The osmotic pressure of this solution at {tex} 300\,\mathrm { K } {/tex} is found to be {tex} 2.57 \times 10 ^ { - 3 } \mathrm { bar } {/tex} . The molar mass of protein will be {tex} \left( R = 0.083 \mathrm { L } \text { bar mol } ^ { - 1 } \mathrm { K } ^ { - 1 } \right) {/tex}

A

{tex} 51022\,\mathrm { g } \,\mathrm { mol } ^ { - 1 } {/tex}

B

{tex}122044\, \mathrm { g }\, \mathrm { mol } ^ { - 1 } {/tex}

C

{tex}31011 \,g\, \mathrm { mol } ^ { - 1 } {/tex}

{tex}61038\, \mathrm { g } \mathrm { mol } ^ { - 1 } {/tex}

Explanation

Q 20.    

Correct4

Incorrect-1

An aqueous solution is 1.00 molal in KI. Which change will cause the vapour pressure of the solution to increase?

A

Addition of NaCl

B

Addition of {tex} \mathrm { Na } _ { 2 } \mathrm { SO } _ { 4 } {/tex}

C

Addition of 1.00 molal {tex} \mathrm { KI } {/tex}

Addition of water

Explanation



Q 21.    

Correct4

Incorrect-1

A solution of sucrose{tex} \left. \text { (molar mass } = 342\, \mathrm { g }\, \mathrm { mol } ^ { - 1 } \right) {/tex} has been prepared by dissolving 68.5{tex} \mathrm { g } {/tex} of sucrose in 1000{tex} \mathrm { g } {/tex} of water. The freezing point of the solution obtained will be {tex} \left( K _ { f } \text { for water } \right. {/tex} {tex} \left. = 1.86 \mathrm { K } \text { kg mol } ^ { - 1 } \right) {/tex}

{tex} - 0.372 ^ { \circ } \mathrm { C } {/tex}

B

{tex} - 0.520 ^ { \circ } \mathrm { C } {/tex}

C

{tex} + 0.372 ^ { \circ } \mathrm { C } {/tex}

D

{tex} - 0.570 ^ { \circ } \mathrm { C } {/tex}

Explanation



Q 22.    

Correct4

Incorrect-1

A 0.0020 {tex} \mathrm { m } {/tex} aqueous solution of an ionic compound {tex} \left[ \mathrm { Co } \left( \mathrm { NH } _ { 3 } \right) _ { 5 } \left( \mathrm { NO } _ { 2 } \right) \right] \mathrm { Cl } {/tex} freezes at {tex} - 0.00732 ^ { \circ } \mathrm { C } {/tex} . Number of moles of ions which 1 mol of ionic compound produces on being dissolved in water will be {tex} \left( K _ { f } = - 1.86 ^ { \circ } \mathrm { C } / \mathrm { m } \right) {/tex}

A

3

B

4

C

1

2

Explanation





Q 23.    

Correct4

Incorrect-1

0.5 molal aqueous solution of a weak acid (HX) is 20{tex} \% {/tex} ionised. If {tex} K _ { f } {/tex} for water is {tex}1.86\, \mathrm { K }\, \mathrm { kg }\, \mathrm { mol } ^ { - 1 } {/tex} , the lowering in freezing point of the solution is

A

{tex}0.56\, \mathrm { K } {/tex}

{tex}1.12\, \mathrm { K } {/tex}

C

{tex} - 0.56\, \mathrm { K } {/tex}

D

{tex} - 1.12\, \mathrm { K } {/tex}

Explanation



Q 24.    

Correct4

Incorrect-1

Concentrated aqueous sulphuric acid is {tex}98 \% \,\mathrm { H } _ { 2 } \mathrm { SO } _ { 4 } {/tex} by mass and has a density of {tex}1.80\, \mathrm { g } \,\mathrm { mL } ^ { - 1 } {/tex} . Volume of acid required to make one litre of {tex}0.1\, \mathrm { M } \mathrm { H } _ { 2 } \mathrm { SO } _ { 4 } {/tex} solution is

A

{tex}16.65\, \mathrm { mL } {/tex}

B

{tex}22.20\, \mathrm { mL } {/tex}

{tex} 5.55\,\mathrm { mL } {/tex}

D

{tex}11.10\, \mathrm { mL } {/tex}

Explanation



Q 25.    

Correct4

Incorrect-1

During osmosis, flow of water through a semipermeable membrane is

A

from solution having lower concentration only

B

from solution having higher concentration only

C

from both sides of semipermeable membrane with equal flow rates

from both sides of semipermeable membrane with unequal flow rates.

Explanation