The average molar heat capacity at constant volume of gaseous mixture contained 2 moles of each of two ideal gases X (C_V , m = $\frac{3}{2}$R) and Y (C_V , m = $\frac{5}{2}$R)

• 2R

• 3R

• 4R

• 8R

How many grams of CaC₂O₄ will dissolve in distilled water to make one litre of saturated solution? Solubility product of CaC₂O₄ is 2.5 x 10^-9 mol² litre^-2 and its molecular weight is 128

• 0.0640 gm

• 0.0032 gm

• 0.0128 gm

• 0.0064 gm

1 g of a non-volatile, non-electrolyte solute of molar mass 250 g/mol was dissolved in 51.2 g of benzene. If the freezing point depression constant , k_f of benzene is 5.12 kg K mol^-1 , the freezing point of benzene is lowered by :

• 0.3 K

• 0.5 K

• 0.2 K

• 0.4 K

A 6% solution of urea is isotonic with :

• 1M solution of glucose

• 0.05 M solution of glucose

• 6% solution of glucose

• 25% solution of glucose

In countries nearer to polar region, the roads are sprinkled with CaCl₂ .This is :

• to minimise the wear and tear of the roads

• to minimise the snow fall

• to minimise pollution

• to minimise the accumulation of dust on the road

The solubility of a gas in water at 300 K under a pressure of 100 atm is 4 x 10^-3 kg L^-1. Therefore, the mass of the gas in kg dissolved 250 mL of water under a pressure of 250 atm at 300 K is :

• 2.5 x 10^-3

• 2.0 x 10^-3

• 1.25 x 10^-3

• 5.0 x 10^-3

The depression in freezing point of 0.1 M aqueous solutions of HCl, CuSO₄ and K₂SO₄ are in the ratio

• 1 : 1 : 1.5

• 1 : 2 : 3

• 1 : 1 : 1

• 2 : 4 : 3

Which of the following pairs of substances cannot exist together in solution?

• Na₂CO₃ + NaOH

• NaHCO₃ + Na₂CO₃

• NaHCO₃ + NaOH

• NaOH + HCl

Assertion : Azeotropic mixtures are formed only by non-ideal solutions and they may have boiling points either greater than both the components or lesser than both the components.

Reason : The composition of the vapour phase is same as that ofthe liquid phase of an azeotropic mixture.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false

• If both assertion and reason are false.

270.

Large difference in boiling points is observed in

• N and P

• P and As

• As and Sb

• Sb and Bi