An aqueous solution of methanol () has a measured molarity of and an absolute density of . What is t — Mole Concept and Some Basic Concepts of Chemistry Chemistry Question

💡 Solution & Explanation

Step 1: Use the interconversion formula relating Molarity ($M$) and Molality ($m$): $m = \frac{1000 \times M}{1000 \times d - M \times M_w}$ where $d$ is density in $\text{g/mL}$ and $M_w$ is molar mass of solute. Step 2: Substitute the known values. $m = \frac{1000 \times 2.45}{1000 \times 0.976 - 2.45 \times 32}$ $m = \frac{2450}{976 - 78.4}$ $m = \frac{2450}{897.6} \approx 2.729\text{ m}$. Rounding to standard significant figures yields $2.73\text{ mol/kg}$.