Phenol dimerizes in benzene. If the observed molecular mass of phenol in solution is 120, its degree — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

Molar mass of phenol (C6H5OH) = 94 g/mol. Observed molar mass M_obs = 120 g/mol. The van 't Hoff factor i = M_normal / M_obs = 94 / 120 ≈ 0.7833. For dimerization: i = 1 - α/2 => 0.7833 = 1 - α/2 => α = 0.433.