Please refer to Solutions MCQ Questions Class 12 Chemistry below. These MCQ questions for Class 12 Chemistry with answers have been designed as per the latest NCERT, CBSE books and syllabus issued for the current academic year. These objective questions for Solutions will help you to prepare for the exams and get more marks.

**Solutions MCQ Questions Class 12 Chemistry**

Please see solved MCQ Questions for Solutions in Class 12 Chemistry. All questions and answers have been prepared by expert faculty of standard 12 based on latest examination guidelines.

**Question. 29.2% (w/W) HCl stock solution has density of 1.25 g mL ^{-1} . The molecular weight of HCl is 36.5 mol^{-1} . The volume (mL) of stock solution required to prepare a 200 mL solution 0.4 M HCl is **

(a) 5.0 mL

(b) 6.0 mL

(c) 8.0 mL

(d) 15.0 mL

## Answer

C

**Question. Two solutions of HCl, A and B have concentrations of 0.5 N and 0.1 M respectively. The volume of solutions A and B required to make 2L of 0.2 N HCl are **

(a) 0.5 L of A + 1.5 L of B

(b) 1.5 L of A + 0.5 L of B

(c) 1.0 L of A + 1.0 L of B

(d) 0.75 L of A + 1.25 Lof B

## Answer

A

**Question. Molality of 2.5 g of ethanoic acid (CH _{3}COOH) in 75 g of benzene is**

(a) 0.565 mol/kg

(b) 0.656 mol/kg

(c) 0.556 mol/kg

(d) 0.665 mol/kg

## Answer

C

**Question. Find the molarity of the solution containing 5.3 g of Na _{2}CO_{3} in 500 mL solution**

(a) 1.0 M

(b) 0.1 M

(c) 0.25 M

(d) 0.2 M

## Answer

B

**Question. Which of the following will represent the normality of 10% ( w/V) acetic acid?**

(a) 1.66 N

(b) 16.6 N

(c) 3.32 N

(d) 33.2 N

## Answer

A

**Question. An aqueous solution of phosphoric acid, H _{3}PO_{4} being titrated has molarity equal to 0.25 M. Which of the following could be nom,ality of this solution? **

(a) 0.25 N

(b) 0.50 N

(c) 0.75 N

(d) All of these

## Answer

D

**Question. 25 mL of 3.0 M HCl are mixed with 75 mL of 4.0 M HCI. If the volumes are additive, the molarity of the final mixture will be **

(a) 4.0 M

(c) 4.25 M

(b) 3.75 M

(d) 3.50 M

## Answer

B

**Question. The molarity of a solution obtained by mixing 750 mL of 0.5 (M) HCI with 250 mL of 2(M) HCl will be**

(a) 0.875 M

(b) 1.00 M

(c) 1.75 M

(d) 0.0975 M

## Answer

A

**Question. Isotonic solutions have equal**

(a) vapour pressure

(b) osmotic pressure

(c) boiling point

(d) freezing point

## Answer

B

**Question. In countries nearer to polar region, the roads are sprinkled with CaCI _{2}. This is **

(a) to minimise the wear and tear of the roads

(b) to minimise the snow fall

(c) to minimise pollution

(d) to minimise the accumulation of dust on the road

## Answer

A

**Question. A 1% solution of KCl (I), NaCl (II), BaCl _{2} (III) and urea (IV) have their osmotic pressure at the same temperature in the ascending order (molar masses of NaCl, KCl, BaCl_{2} and urea are respectively 58.5, 74.5, 208.4 and 60 g.mol^{-1}) . Assume 100% ionisation of the electrolytes at this temperature **

(a) I < III < II < IV

(b) III < I< II< IV

(c) I < II < III < IV

(d) I < III < IV < II

(e) III < IV < I < II

## Answer

E

**Question. The sum of mole fractions of A, B and C in an aqueous solution containing 0.2 moles of each A, B and C is**

(a) 0.6

(b) 0.2

(c) 1.0

(d) 1.2

## Answer

C

**Question. Calculate the nomrnlity of 250 m.L aqueous solution of H _{2}SO_{4} having pH= 0.00. **

(a) 0.25 N

(b) 0.50 N

(c) 1 N

(d) 2 N

## Answer

B

**Question. What is the molarity of 0.2 N Na _{2}CO_{3} solution ?**

(a) 0.1 M

(b) 0 M

(c) 0.4 M

(d) 0.2 M

## Answer

A

**Question. A mixtw·e of ethane and ethene occupies 41 L at 1 atm and 500 K. The mixture reacts completely with 10/3 mole of O _{2} to produce CO_{2} and H_{2}O. The mole fraction of ethane and ethene in the mixtw·e are**

**R = 0.082L atm K**

^{-1}mol^{-1}) respectively(a) 0.50, 0.50

(b) 0.75, 0.25

(c) 0.67, 0.33

(d) 0.25, 0.75

(e) 0.33, 0.67

## Answer

C

**Question. The density of a 3M sodium thiosulphate (Na _{2}S_{2}O_{3} ) solution is 1.25 g/mL. Calculate the per cent by weight of sodium thiosulphate. **

(a) 12.65%

(b) 37.92%

(c) 0.87%

(d) 63.21%

## Answer

B

**Question. Dissolving 120 g of urea (mol. wt. 60) in 1000 g of water gave a solution of density 1.15 g/mL. The molarity of the solution is **

(a) 1.78 M

(b) 2.00 M

(c) 2.05 M

(d) 2.22 M

## Answer

C

**Question. 25 cm ^{3} of oxalic acid completely neutralise 0.064 g of sodium hydroxide. Molarity of the oxalic acid solution is**

(a) 0.064

(b) 0.045

(c) 0.015

(d) 0.032

## Answer

D

**Question. How many grams of sulphuric acid is to be dissolved to prepare 200 mL aqueous solution having concentration of [H _{3}O^{+}] ions 1 Mat 25°C temperature.**

**[H = 1, 0 = 16, S = 32 g .mol**

^{-1}](a) 4.9g

(b) 19.6g

(c) 9.8g

(d) 0.98 g

## Answer

C

**Question. 50 cm ^{3} of 0.2 N HCI is titrated against 0.1 N NaOH solution. The titration is discontinued after adding 50 cm^{3} ofNaOH. The remaining titration is completed by adding 0.5 N KOH. The volume of KOH required for completing the titration is **

(a) 12 cm

^{3}

(b) 10 cm

^{3}

(c) 25 cm

^{3}

(d) 10.5cm

^{3 }

## Answer

B

**Question. The Henry’s law constant for the solubility of N _{2} gas in water at 298 K is 1.0 x 105 atrn. The mole fraction of N_{2} in air is 0.8. The number ofmols of N_{2} from air dissolved in 10 moles of water of 298 Kand 5 atm pressure is**

(a) 4 x 10

^{-4}

(b) 4. 0 x 10

^{-5}

(c) 5.0 x 10

^{-4}

(d) 4 .0 x 10

^{-6 }

## Answer

A

**Question. Out of following which one is not an example of a solution? **

(a) Air

(b) Brass

(c) Amalgam

(d) Benzene in water

## Answer

D

**Question. The volume of 0.1 M oxalic acid that can be completely oxidised by 20 mL of 0.025 M KMnO _{4} solution is**

(a) 25 mL

(b) 12.5 mL

(c) 37.5 mL

(d) 125 mL

## Answer

B

**Question. A 5.2 molal aqueous solution of methyl alcohol, CH _{3}OH, is supplied. What is the mole fraction of methyl alcohol in the solution ? **

(a) 1.100

(b) 0.190

(c) 0.086

(d) 0.050

## Answer

C

**Question. The molality of a urea solution in which 0.0100 g of urea, [(NH _{2})_{2} CO] is added to 0.3000 dm^{2} of water at STP is**

(a) 0.555 m

(b) 5.55 x 10

^{-4}m

(c) 33.3 m

(d) 3.33 x 10

^{-2}m

## Answer

B

**Question. What is the total number of moles of H _{2}SO_{4} needed to prepare 5.0 L ofa 2.0 M solution of H_{2}SO_{4}? **

(a) 2.5

(b) 5.0

(c) 10

(d) 20

## Answer

C

**Question. 2.5 L of NaCl solution contain 5 moles of the solute. What is the molarity ? **

(a) 5 M

(b) 2 M

(c) 2.5 M

(d) 12.5 M

## Answer

B

**Question. Which of the following concentration factors is affected by change in temperature ?**

(a) Molarity

(b) Molality

(c) Mole fraction

(d) Weight fraction

## Answer

A

**Question. How many grams of NaOH will be required to prepare 500 g solution containing 10% w/w NaOH solution ?**

(a) 100 g

(b) 50 g

(c) 0.5 g

(d) 5.0 g

## Answer

B

**Question. 10cm ^{3} of 0.1 Nmonobasicacidrequires 15cm^{3} ofsodium hydroxide solution whose normality is **

(a) 1.5 N

(b) 0.15 N

(c) 0.066 N

(d) 0.66 N

## Answer

C

**Question. 2 N HCI solution will have same molar concentration as a**

(a) 4.0 N H_{2}SO_{4}

(c) 1 NH_{2}SO_{4}

(b) 0.5 N H_{2}SO_{4 }

(d) 2 NH_{2}SO_{4 }

## Answer

A

**Question. What is the molality of pure water ? **

(a) 1

(b) 18

(c) 55.5

(d) None of these

## Answer

C

**Question. 25 mL of a solution of barium hydroxide on titration with 0.1 molar solution of hydrochloric acid gave a titre value of 35 m.L. The molarity of barium hydroxide solution was**

(a) 0.07

(b) 0.14

(c) 0.28

(d) 0.35

## Answer

A

**Question. Molarity ofa given orthophosphoric acid solution is 3M. It’s n01m ality is **

(a) 9 N

(b) 0.3 N

(c) 3 N

(d) 1 N

## Answer

A

**Question. In which ratio of volume 0.4 M HCI and 0.9 M HCl are to be mixed such that the concentration of the resultant solution becomes 0.7 M?**

(a) 4 : 9

(b) 2 : 3

(c) 3 : 2

(d) 1 : 1

## Answer

B

**Question. Two bottles A and B contains 1M and 1 m aqueous solution of sulphuric acid respectively **

(a) A is more concentrated than B

(b) B is more concentrated than A

(c) concentration of A is equal to concentration of B

(d) it is not possible to compare the concentrations

## Answer

A

**Question. Molarity is expressed as**

(a) L/mol

(b) mol/L

(c) mol/1000 g

(d) g/L

## Answer

B

**Question. Two liquids X and Y form an ideal solution. The mixture has a vapour pressure of 400 mm at 300 K when mixed in the molar ratio ofl : 1 and a vapour pressure of 350 mm when mixed in the molar ratio of 1 : 2 at the same temperature. The vapour pressures of the two pure liquids X and Y respectively are **

(a) 250 mm, 550 mm

(b) 350 mm, 450 mm

(c) 350 mm, 700 mm

(d) 500 mm, 500 mm

(e) 550 mm, 250 mm

## Answer

E

**Question. Vapour pressure of pure A = 100 torr, moles = 2; vapour pressure of pure B = 80 torr, moles = 3. Total vapour pressure of the mixture is **

(a) 440 torr

(b) 460 torr

(c) 180 torr

(d) 88 torr

## Answer

D

**Question. Equal masses of methane and oxygen are mixed in an empty container at 25°C. The fraction of the total pressure exerted by oxygen is**

(a) 2/3

(b) 1/3 x 273/298

(c) 1/3

(d) 1/2

## Answer

C

**Question. Which of the following will show a negative deviation from Raoult’s law? **

(a) Acetone-benzene

(b) Acetone-ethanol

(c) Benzene-methanol

(d) Acetone-chloroform

## Answer

D

**Question. A solution of two liquids boils at a temperature more than the boiling point of either them. Hence, the binary solution shows**

(a) negative deviation from Raoult’s law

(b) positive deviation from Raoult’s law

(c) no deviation from Raoult’s law

(d) positive or negative deviation from Raoult’s law depending upon the composition

## Answer

A

**Question. A binary liquid solution is prepared by mixing n-heptane and ethanol. Which one of the following statements is correct regarding the behaviour of the solution ? **

(a) The solution formed is an ideal solution

(b) The solution is non-ideal, showing positive deviation from Raoult’s law

(c) The solution is non-ideal, showing negative deviation from Raoult’s law

(d) n-heptane shows positive deviation while ethanol show negative deviation from Raoult’s law

## Answer

B

**Question. Vapour pressure of pure ‘A’ is 70 mm of Hg at 25°C. It fom1s an ideal solution with ‘B’ in which mole fraction of A is 0.8. If the vapour pressure of the solution is 84 mm of Hg at 25°C, the vapour pressure of pure ‘B’ at 25°C is**

(a) 28 mm

(b) 56 mm

(c) 70 mm

(d) 140 mm

## Answer

D

**Question. A mixture of ethyl alcohol and propyl alcohol has a vapour pressure of 290 mm at 300 K The vapour pressure of propyl alcohol is 200 mm. If the mole fraction of ethyl alcohol is 0.6, its vapour pressure (in mm) at the same temperature will be **

(a) 350

(b) 300

(c) 700

(d) 360

## Answer

A

**Question. The volume of 10 N and 4 N HCI required to make 1 L of 7 N HCI are **

(a) 0.50 L of 10 N HCI and 0.50 L of 4 N HCI

(b) 0.60 L of 10 N HCI and 0.40 L of 4 N HCI

(c) 0.80 L of 10 N HCI and 0.20 L of 4 N HCI

(d) 0.75 L of 10 N HCI and 0.25 L of 4 N HCI

## Answer

A

**Question. At STP, a container has l mole of Ar, 2 moles of CO _{2} , 3 moles of O_{2} and 4 moles of N_{2} . Without changing the total pressure if one mole of O_{2} is removed, the partial pressure of O_{2} is**

(a) changed by about 16%

(b) halved

(c) changed by 26%

(d) unchanged

## Answer

C

**Question. 138 gofethyl alcohol is mixed with 72 gofwater. The ratio of mole fraction of alcohol to water is **

(a) 3 : 4

(b) 1 : 2

(c) 1 : 4

(d) 1 : 1

## Answer

A

**Question. An aqueous solution of glucose is 20% in strength. The volume in which 1 g-mole of it is dissolved will be**

(a) 9 L

(b) 1.8 L

(c) 8 L

(d) 0.9 L

## Answer

D

**Question. A solution contains 1. 2046 x 10 ^{24} hydrochloric acid molecules in 1 dm^{3} of the solution. The strength of the solution is **

(a) 6 N

(b) 2 N

(c) 4 N

(d) 8 N

## Answer

B

**Question. 35.4 mL of HCI is required for the neutralisation of a solution containing 0.275 g of sodium hydroxide. The normality of hydrochloric acid is **

(a) 0.97N

(b) 0.142N

(c) 0.194N

(d) 0.244N

## Answer

C

**Question. One part of solute expressed as in one million parts of solvent is**

(a) ppm

(b) mg/100 cc

(c) g/L

(d) g/100 cc

## Answer

A

**Question. The molarity of the solution obtained by dissolving 2.5g of NaCl in 100 mL of water is **

(a) 0.00428 moles

(b) 428 moles

(c) 0.428 moles

(d) 0.0428 moles

## Answer

C

**Question. Which one is correct? **

(a) Molality changes with temperaure

(b) Molality does not change with temperature.

(c) Molarity does not change with temperature.

(d) Normality does not change with temperature.

## Answer

B

**Question. Volume of water needed to mix with 10 mL solution of 1 N HCI to get 0.1 N HCI is**

(a) 900 mL

(b) 9 mL

(c) 90 mL

(d) 100 mL

## Answer

C

**Question. Equal moles of water and urea are taken in a flask. What is mass percentage of urea in the solution?**

(a) 23.077%

(b) 230.77%

(c) 2.3077%

(d) 0.23077%

## Answer

A

**Question. What is molarity of K+ in aqueous solution that contains 17.4 ppm of K _{2}SO_{4} (174 gmol^{-1})? **

(a) 2 x 10

^{-2}M

(b) 2 x 10

^{-3}M

(c) 4 x 10

^{-4}M

(d) 2 x 10

^{-4}M

## Answer

D

**Question. Assuming that sea water is a 3.50 weight per cent aqueous solution of NaCl. What is the molality of sea water ?**

(a) 0.062 m

(b) 0.0062 m

(c) 0.62 m

(d) 6.2 m

## Answer

C

**Question. If the osmotic pressure of a 0.010 M aqueous solution of sucrose at 27° Cis 0.25 atm, then the osmotic pressure of a 0.010 M aqueous solution of NaCl at 27° C is**

(a) 0.062 atm

(b) 0.12 atm

(c) 0.25 atm

(d) 0.50 atm

## Answer

D

**Question. A solution of 1.25 g of P in 50 g of water lower freezing point by 0.3° C Molar mass of P is 94,****K _{f} (water)= 1.86 K kg mol^{-1} . The degree of association of P in water is **

(a) 80%

(b) 60%

(c) 65%

(d) 75%

## Answer

A

**Question. 5 L of a solution contains 25 mg of CaCO _{3} . What is its concentration in ppm? (mol. wt. of CaCO_{3} is 100)**

(a) 25

(b) 1

(c) 5

(d) 2500

## Answer

C

**Question. Two solutions of a substance (non-electrolyte) are mixed in the following manner. 480 mL of 1.5 M (first solution) + 520mL of 1.2 M second solution. What is the molarity of the final mixture ?**

(a) 2.70 M

(b) 1.344 M

(c) 1.50 M

(d) 1.20 M

## Answer

B

**Question. Molarity of 0.2 N H _{2}SO_{4} is**

(a) 0.2

(b) 0.4

(c) 0.6

(d) 0.1

## Answer

D

**Question. 40% by weight solution will contain how much mass of the solute in 1L solution, density of the solution is 1.2 g/mL?**

(a) 480 g

(b) 48 g

(c) 38 g

(d) 380 g

## Answer

A

**Question. To neutralise completely 20 mL of0.1 M aqueous solution of phosphorous acid (H _{3}PO_{3}) the volume of 0.1 M aqueous KOH solution required is**

(a) 10 mL

(b) 20 mL

(c) 40 mL

(d) 60 mL

## Answer

C

**Question. How many moles of Al _{2} (SO_{4})_{3} would be in 50 g of the substance ?**

(a) 0.083 mol

(c) 0.481 mol

(b) 0.952 mol

(d) 0.140 mol

## Answer

D

**Question. Density of a 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is **

(a) 1.14 mol kg^{-1}

(b) 3.28 mol kg^{-1}

(c) 2.28 mol kg^{-1}

(d) 0.44 mol kg^{-1}

## Answer

C

**Question. A 5 molar solution of H _{2}SO_{4} is diluted from 1 L to 10 L. What is the normality of the solution? **

(a) 0.25N

(b) 1 N

(c) 2 N

(d) 7 N

## Answer

B

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

(a) Molarity

(b) Molarity and mole fraction

(c) Mole fraction and molality

(d) Molality and normality

(e) Only molality

## Answer

C

**Question. A solution is prepared by dissolving 24.5 g of sodium hydroxide in distilled water to give IL solution. The molarity of NaOH in the solution is ****(Given, that molar mass of NaOH = 40.0g mol ^{– 1})**

(a) 0.2450 M

(b) 0.6125 M

(c) 0.9800 M

(d) 1.6326 M

## Answer

D

**Question. Consider separate solution of 0.500 M C _{2}H_{5}OH(aq), 0.100 M Mg^{3} (PO_{4} )_{2 }(aq), 0.250 M KBr (aq)and0.125 M Na_{3}PO_{4} (aq)i at 25° C. Which statement is true about these solution assuming all salts to be strong electrolytes. **

(a) They all have same osmotic pressure

(b) 0.100 M Mg

_{3}(PO

_{4 })

_{2}(aq) has the highest osmotic pressure

(c) 0.125 M Na

_{3}PO

_{4}(aq) has the highest osmotic pressure

(d) 0.500 M C

_{2}H

_{5}OH(aq) has the highest osmotic pressure

## Answer

A

**Question. If the elevation in boiling point of a solution of 10 g of solute (mol. wt= 100) in 100 g of water is ΔT _{b}, the ebullioscopic constant of water is **

(a) 10

(b) 100T

_{b}

(c) ΔT

_{b}

(d) ΔT

_{b}/10

## Answer

C

**Question. Glucose is mixed in 1 litre water, the ratio of ΔT _{f} / K_{f} changed to 10^{-3} . The mass of glucose (C_{6}H_{12}O_{6} ) is**

(a) 180 gram

(b) 18 gram

(c) 1.8 gram

(d) 0.18 gram

## Answer

D

**Question. The molar mass of a solute X in g mol ^{-1} ,if its 1 % solution is isotonic with a 5% solution of cane sugar (molar mass = 342g mol^{-1}) is **

(a) 68.4

(b) 34.2

(c) 136.2

(d) 171.2

## Answer

A

**Question. The volume of water to be added to N / 2 HCl to prepare 500cm ^{3} of N / 10 solution is**

(a) 450 cm

^{3}

(b) 100 cm

^{3}

(c) 45 cm

^{3}

(d) 400 cm

^{3}

## Answer

D

**Question. Molar solution means 1 mole of solute present in **

(a) 1000 g of solvent

(b) 1 L of solvent

(c) 1 L of solution

(d) 1000 g of solution

## Answer

C

**Question. Find the boiling point of a solution of 5.00 g ofnapthalene (C _{10}H_{8} ) in 100 g of benzene. Kb of benzene if 2.53° elm the nom1al boiling point of benzene = 80° C **

(a) 81°C

(b) 85°C

(c) 0.9°C

(d) 79°C

## Answer

A

**Question. Which among the following is a non-colligative property**

(a) elevation in boiling point

(b) osmotic pressure

(c) refractive index

(d) lowering of vapour pressure

## Answer

C