A 5 % solution (by mass) of cane sugar in water has freezing point of 271 K. Freezing point of 5 % glucose in water would be -

(freezing point of pure water is 273.15 K)

1. 279.24 K

2. - 269.06 K

3. 275. 42 ^oC

4. 269.06 K

Two elements A and B form compounds having formula AB₂ and AB₄. When dissolved in 20 g of benzene (C₆H₆), 1 g of AB₂ lowers the freezing point by 2.3 K whereas 1.0 g of AB₄ lowers it by 1.3 K. The atomic masses of A and B are respectively -

(K_f for benzene is 5.1 K kg mol^-1)

1. 15.59 u and 52.64 u

2. 25.59 u and 42.64 u

3. 13.59 u and 52.64 u

4. 23.59 u and 32.64 u

The depression in the freezing point of water when 10 g of CH₃CH₂CHClCOOH is added to 250 g of water will be -

 (K_a = 1.4 × 10^–3, K_f = 1.86 K kg mol^-1)

1. 0.32 K

2. 2.87 K

3. 0.65 K

4. 5.03 K