MCQ Chapter 2 Solutions Class 12 Chemistry

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

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

Question. Molality of 2.5 g of ethanoic acid (CH₃COOH) 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

Question. Find the molarity of the solution containing 5.3 g of Na₂CO₃ in 500 mL solution
(a) 1.0 M
(b) 0.1 M 
(c) 0.25 M
(d) 0.2 M

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

Question. An aqueous solution of phosphoric acid, H₃PO₄ 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

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

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

Question. Isotonic solutions have equal
(a) vapour pressure
(b) osmotic pressure
(c) boiling point
(d) freezing point

Question. In countries nearer to polar region, the roads are sprinkled with CaCI₂. 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

Question. A 1% solution of KCl (I), NaCl (II), BaCl₂ (III) and urea (IV) have their osmotic pressure at the same temperature in the ascending order (molar masses of NaCl, KCl, BaCl₂ 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

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

Question. Calculate the nomrnlity of 250 m.L aqueous solution of H₂SO₄ having pH= 0.00. 
(a) 0.25 N
(b) 0.50 N
(c) 1 N
(d) 2 N

Question. What is the molarity of 0.2 N Na₂CO₃ solution ?
(a) 0.1 M
(b) 0 M
(c) 0.4 M
(d) 0.2 M

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 O₂ to produce CO₂ and H₂O. 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

Question. The density of a 3M sodium thiosulphate (Na₂S₂O₃ ) 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%

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

Question. 25 cm³ 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

Question. How many grams of sulphuric acid is to be dissolved to prepare 200 mL aqueous solution having concentration of [H₃O⁺] 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

Question. 50 cm³ of 0.2 N HCI is titrated against 0.1 N NaOH solution. The titration is discontinued after adding 50 cm³ ofNaOH. The remaining titration is completed by adding 0.5 N KOH. The volume of KOH required for completing the titration is 
(a) 12 cm³
(b) 10 cm³
(c) 25 cm³
(d) 10.5cm³

Question. The Henry’s law constant for the solubility of N₂ gas in water at 298 K is 1.0 x 105 atrn. The mole fraction of N₂ in air is 0.8. The number ofmols of N₂ 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

Question. Out of following which one is not an example of a solution? 
(a) Air
(b) Brass
(c) Amalgam
(d) Benzene in water

Question. The volume of 0.1 M oxalic acid that can be completely oxidised by 20 mL of 0.025 M KMnO₄ solution is
(a) 25 mL
(b) 12.5 mL 
(c) 37.5 mL
(d) 125 mL

Question. A 5.2 molal aqueous solution of methyl alcohol, CH₃OH, 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

Question. The molality of a urea solution in which 0.0100 g of urea, [(NH₂)₂ CO] is added to 0.3000 dm² 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

Question. What is the total number of moles of H₂SO₄ needed to prepare 5.0 L ofa 2.0 M solution of H₂SO₄? 
(a) 2.5
(b) 5.0
(c) 10
(d) 20

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

Question. Which of the following concentration factors is affected by change in temperature ?
(a) Molarity
(b) Molality
(c) Mole fraction
(d) Weight fraction

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

Question. 10cm³ of 0.1 Nmonobasicacidrequires 15cm³ ofsodium hydroxide solution whose normality is 
(a) 1.5 N
(b) 0.15 N
(c) 0.066 N
(d) 0.66 N

Question. 2 N HCI solution will have same molar concentration as a
(a) 4.0 N H₂SO₄
(c) 1 NH₂SO₄
(b) 0.5 N H₂SO₄ 
(d) 2 NH₂SO₄

Question. What is the molality of pure water ? 
(a) 1
(b) 18
(c) 55.5
(d) None of these

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

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

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

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

Question. Molarity is expressed as
(a) L/mol
(b) mol/L
(c) mol/1000 g
(d) g/L

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       

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         

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     

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     

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     

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     

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     

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         

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

Question. At STP, a container has l mole of Ar, 2 moles of CO₂ , 3 moles of O₂ and 4 moles of N₂ . Without changing the total pressure if one mole of O₂ is removed, the partial pressure of O₂ is
(a) changed by about 16%
(b) halved
(c) changed by 26%
(d) unchanged

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

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

Question. A solution contains 1. 2046 x 10²⁴ hydrochloric acid molecules in 1 dm³ of the solution. The strength of the solution is 
(a) 6 N
(b) 2 N
(c) 4 N
(d) 8 N

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

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

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

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.

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

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%

Question. What is molarity of K+ in aqueous solution that contains 17.4 ppm of K₂SO₄ (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

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

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

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%

Question. 5 L of a solution contains 25 mg of CaCO₃ . What is its concentration in ppm? (mol. wt. of CaCO₃ is 100)
(a) 25
(b) 1
(c) 5
(d) 2500

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

Question. Molarity of 0.2 N H₂SO₄ is
(a) 0.2
(b) 0.4
(c) 0.6
(d) 0.1

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

Question. To neutralise completely 20 mL of0.1 M aqueous solution of phosphorous acid (H₃PO₃) the volume of 0.1 M aqueous KOH solution required is
(a) 10 mL
(b) 20 mL
(c) 40 mL
(d) 60 mL

Question. How many moles of Al₂ (SO₄)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

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

Question. A 5 molar solution of H₂SO₄ 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

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

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

Question. Consider separate solution of 0.500 M C₂H₅OH(aq), 0.100 M Mg³ (PO₄ )₂ (aq), 0.250 M KBr (aq)and0.125 M Na₃PO₄ (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 Mg₃ (PO₄ )₂ (aq) has the highest osmotic pressure
(c) 0.125 M Na₃ PO₄ (aq) has the highest osmotic pressure
(d) 0.500 M C₂H₅OH(aq) has the highest osmotic pressure

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

Question. Glucose is mixed in 1 litre water, the ratio of ΔT_f / K_f changed to 10^-3 . The mass of glucose (C₆H₁₂O₆ ) is
(a) 180 gram
(b) 18 gram 
(c) 1.8 gram
(d) 0.18 gram

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

Question. The volume of water to be added to N / 2 HCl to prepare 500cm³ of N / 10 solution is
(a) 450 cm³
(b) 100 cm³
(c) 45 cm³
(d) 400 cm³

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

Question. Find the boiling point of a solution of 5.00 g ofnapthalene (C₁₀H₈ ) 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

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