# How many atoms of nitrogen are in 10 g of "NH"_4"NO"_3?

Nov 10, 2016

$5$

#### Explanation:

In order to find out how many atoms we have in a certain amount of a sample, we have to use the Avogadro constant: the number of atoms in one mole, ${N}_{\text{A}}$, is equal to $6.02 \times {10}^{23}$.

In order to work out how many moles we have in our sample, we can use the formula $\text{n (moles)"="m (mass)"/"Mr (molar mass)}$.

$\text{n} = \frac{10}{80} = 0.125$

${N}_{\text{A}} = 0.125 \times 6.02 \times {10}^{23} = {7.525}^{23}$