What is the mole fraction of the solute in a (molal) aqueous solution? — Solutions and Colligative Properties Chemistry Question

💡 Solution & Explanation

A $1.00\text{ m}$ aqueous solution means $1\text{ mole}$ of solute is dissolved in $1\text{ kg}$ ($1000\text{ g}$) of water. Moles of $H_2O = \frac{1000}{18} = 55.55\text{ moles}$. Total moles = $1 + 55.55 = 56.55$. Mole fraction of solute = $\frac{1}{56.55} = 0.01768 \approx 0.0177$.