# How would the volume of an 18*g mass of water change if its temperature changed by over 100 ""^@C?

$18 \cdot g$ clearly constitutes a mole of water. However, the water can be condensed or in the gaseous phase. Water is quite involatile, and $18 \cdot g$ of ice or water indeed contains a molar quantity of $O {H}_{2}$ molecules, i.e. $2 \times {N}_{A}$ $H$ atoms, and ${N}_{A}$ $O$ atoms; $18 \cdot g$ in total.
At normal pressures, if we heat the water up over $100$ ""^@C, a phase change occurs, and the water enters the gaseous phase. And $18 \cdot g$ of GASEOUS water would indeed occupy $22.4 \cdot L$....of course the temperature of the gas phase would also change the volume.