Solute A associates in water. When 0 . 7   g of solute A is dissolved in 42 . 0   g of water, it…

Solute A associates in water. When 0.7 g of solute A is dissolved in 42.0 g of water, it depresses the freezing point by 0.2 °C. The percentage association of solute A in water, is

[Given: Molar mass of A=93 g mol-1. Molal depression constant of water is 1.86 K kg mol-1]

  1. 50%
  2. 60%
  3. 70%
  4. 80%

Solution

Depression in freezing point,ΔTf=iKf×m

2.0=ix1.86×7×100093×42

2.0=i3.33

i=0.6

i=1+1n-1β

0.6=1+12-1β

β=0.8

%β=80

Hence, the percentage association of solute A in water is 80.

Asked in: JEE Main 2022 (25 Jun Shift 2)

Practice more Solutions questions on Aicharya