# What is the mass of two moles of oxygen gas(O2)?

$\text{63.9976 g}$
One mole of oxygen is $\text{15.9994 g}$, but because oxygen is a diatomic molecule, it is bonded with itself. So,
$\text{15.9994 g" * 2 = "31.9988 g}$
per mole of oxygen. From here, the answer is simple. Just multiply $2$ by $\text{31.9988 g}$ because there are two moles of oxygen. So, the answer is $\text{63.9976 g}$..