# What is the "molality" of a 200*g mass of sugar dissolved in a mass of 100*g of water?

Jun 10, 2017

Well, we can work out its $\text{molality}$ directly.........

#### Explanation:

$\text{Molality"="Moles of solute"/"Kilograms of solvent}$

And here $\text{Molality} = \frac{\frac{200 \cdot g}{180.16 \cdot g \cdot m o {l}^{-} 1}}{0.100 \cdot k g} = 11.1 \cdot m o l \cdot k g$.

We would normally express concentration in the more familiar terms of $\text{molarity}$, where $\text{molarity"="Moles of solute (mol)"/"Volume of solution (L)}$.

We would expect here that the volume of solution would differ somewhat in each scenario (the difference might be slight!). Do you appreciate the distinction I am trying to make.