# How many moles of sodium oxide will be produced when 10 moles of sodium react with oxygen?

Mar 24, 2017

${\text{2.5 mol O}}_{2}$

#### Explanation:

First, write a balanced equation

$4 \text{Na" + "O"_2 -> 2"Na"_2"O}$

Then multiply the mols of $\text{Na}$ given in the question by the mol ratio. In this case, the mole ratio is

$\left(\text{1 mol O"_2) / ("4 mol Na}\right)$

Remember what you want in the answer should be in the numerator and what is given in the question should be in the denominator so it cancels out.

10 cancel("mol Na") * ("1 mol O"_2) / (4 cancel("mol Na")) = "2.5 mol O"_2