Chemistry Question Bank

Assertion: Molecular mass of benzoic acid when determined by colligative properties is found high. Reason: Dimerisation of benzoic acid.

The vapour pressure lowering caused by the addition of 100 g of sucrose (molecular mass = 342) to 1000 g of water (if the vapour pressure of water at 250C is 23.8 mm Hg) is (AFMC 2012)

The empirical formula of a non-electrolyte is CH₂O. A solution containing 3 g of the compound exerts the same osmotic pressure as that of 0.05 M glucose solution. The molecular formula of the compound is (KCET 2011)

The mass of non-volatile solute of molar mass 40 g/mol that should be dissolved in 114 g of octane to lower its vapour pressure by 20% is (KCET 2012)

0.1 M NaCl and 0.05 M BaC₁₂ solutions are separated by a semipermeable membrane in a container. For this system, choose the correct answer. (AMU 2010)

The boiling point of water is 1000C. What will be the boiling point of an aqueous solution containing 0.6 g of urea (molar mass = 60) in 100 of water? b k for water 0.52 K / m (RPMT 2010) (a) o 100.052 C (b) o 101.052…

The relative lowering of vapour pressure is equal to the ratio between the number of (BVP 2010)

Of the following 0.10 m aqueous solutions, which one will exhibit the largest freezing point depression? (AIPMT 2014)

An aqueous solution is 1.0 molal in KI. Which change will cause the vapour pressure of the solution to increase? (AIPMT 2010)

25.3 g of sodium carbonate, Na₂CO₃ is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentration of sodium ion and carbonate ions respectively are (Molar mass…

A solution of sucrose (molar mass = 342g mol -l) has been prepared by dissolving 68.5g of sucrose in 1000g of water. The freezing point of the solution obtained will be (Kf for water = 1.86 K Kg mol-l) (AFMC 2010) (a)…

Assertion: 1.575g H₂C₂O₄.2H₂O in 250 mL solution makes it 0.1 N. Reason : H₂C₂O₄.2H₂O is a dihydrate organic acid.

60 mL of N/5 H₂SO₄, 10 mL of N/2 HNO₃ and 30 mL of N/10 HCl are mixed together. The strength of the resulting mixture is (UP CPMT 2009)

Calculate the mass of urea (NH₂CONH₂) required in making 0.25 molal aqueous solution using 2.5 L water. (Haryana PMT 2010)

If the elevation in boiling point of a solution of 10 g of solute (molecular weight = 100) in 100 g of water is b T , the ebulliscopic constant of water is (Manipal 2010)

To observe an elevation in boiling point of 0.050C, the amount of a solute (molecular weight = 100) to be added to 100 g of water (Kb =0.5) is (WB JEE 2014)

If is degree of dissociation of Na₂SO₄, the van’t Hoff’s factor, i, used for calculating the molar mass is

If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water ( Tf), when 0.01 mole of sodium sulphate is dissolved in 1 kg of water, …

0.2 molal acid HX ionises 20%. Kf for acid is 1.86 molality–1. Freezing point is

Van’t Hoff factor of Ca (NO₃)₂ is

Which of the following aqueous solutions has the highest boiling point?

0.01 M solution each of urea, common salt and Na₂SO₄ are taken, the ratio of depression of freezing point is

At o 25 C, the total pressure of an ideal solution obtained by mixing 3 moles of ‘A’ and 2 moles of ‘B’, is 184 torr. What is the vapour pressure (in torr) of pure ‘B’ at the same temperature? (Vapour pressure of pure…

Which one of the following statements is false?

The freezing point (in ºC) of solution containing 0.04g of AlCl₃ (mol. wt. 133) in 100g of water (Kf = 1.86 K kg mol–1) is