# What is the mass of 0.35 moles of oxygen gas molecules?

Jan 20, 2018

The answer is: $\text{11 g}$.

#### Explanation:

$n = \frac{m}{M}$

Where $n$ = number of moles, $m$ = mass in grams and $M$ = molar mass.

We know the molar mass of ${O}_{2}$ is 32.00 g/mol
i.e. 2 $\times$ 16 g, the molar mass of one oxygen atom ($O$)

We can rearrange the formula to:
$m = n M$

$\text{mass" = "0.35 mol" xx "32.00 g/mol" = "11 g} \to$ two sig figs