The molal elevation constant for water is 0.52^ C kg mol ⁻¹ . Find out the boiling point of solution when 6.0 g of urea is dissolved in 200 g of water. (molar mass of urea = 60 g/mol)

Step-by-step solution

Given: Mass of urea, w₂ = 6.0 g Molar mass of urea, M₂ = 60 g/mol Mass of water, w₁ = 200 g = 0.2 kg Molal elevation constant, K_b = 0.52^ C kg mol ⁻¹ Number of moles of urea is: n = w₂ M₂ = 6.0 60 = 0.1 mol Molality of the solution is: m = n w₁ (in kg) = 0.1 0.2 = 0.5 mol kg ⁻¹ Elevation in boiling point is given by: T_b = K_b m T_b = 0.52 0.5 = 0.26^ C The boiling point of pure water is 100^ C. Therefore, the boiling point of the solution is: T_b = 100 + T_b = 100 + 0.26 = 100.26^ C Answer: 100.26^ C