# What is the weight of the oxygen element in 10 moles of pure water?

$160 g$
Weight of $1$ mole of pure ${H}_{2} O = 18 g$
Weight of $O$ atoms in $1$ mole of pure ${H}_{2} O = 16 g$
$\therefore$ Weight of $O$ atoms in $10$ moles of pure ${H}_{2} O = 10 \times 16 g = 160 g$