Question

What is the mass of one mole of water?

Answer 1

Given:

Moles of water$\left({\mathrm{H}}_2\mathrm{O}\right)$ $=1\mathrm{mol}$

Step 1: Molar mass of water$\left({\mathrm{H}}_2\mathrm{O}\right)$:

The molar mass of water$=2\times 1+16=18$ $\mathrm{g}{\mathrm{mol}}^{-1}$

Step 2: To determine the mass of one mole of water:

Moles of water$=\frac{\mathrm{Mass}\mathrm{of}\mathrm{water}}{\mathrm{Molar}\mathrm{mass}\mathrm{of}\mathrm{water}}$

Mass of water $=$Moles of water $\times$Molar mass of water

Mass of water$=1\mathrm{mol}\times 18\mathrm{g}{\mathrm{mol}}^{-1}=18\mathrm{g}$

Therefore, the mass of one mole of water is $\mathbf{18}\mathbf{g}$.