Question

Calculate the molal elevation constant for water given that 0.2 molal solution of non-volatile and non-electrolyte solute increases the boiling point of water by 0.104 K.

Options

• 0.104 k

• 0.15 kg mol^–1

• 0.41 kg mol^–1

• 0.52 kg mol^–1

Answer 1

0.52 kg mol^–1 

Explanation:

ΔTb = kb × m or Kb: `(ΔTb)/m`

m = 0.2 m, ΔTb = 0.104 k

kb = `((0.104  k))/((0.2  m))` = 0.52 km^–1 or 0.52 kg mol^–1