# What is the molality of a solution prepared by dissolving 0.100 mol of chloroform, CHCI_3, in 400.0 g of toluene?

$\text{Molality"="Moles of solute"/"Mass of solvent (kg)}$
$\text{Molality} = \frac{0.100 \cdot m o l}{0.4000 \cdot k g} = 0.250 \cdot m o l \cdot k {g}^{-} 1$ with respect to chloroform dissolved in toluene. And of course we could express the molality with respect to toluene dissolved in chloroform.