# How do you calculate the percentage composition of Oxygen in N_2O_5?

Mar 1, 2016

25.93% $N$, 74.07%$O$

#### Explanation:

You first need refrence a periodic table to find the weight of $N$ and $O$

$N$ = $14.0 g$
$O$ = $16.0 g$

Multiply each element based on how many of each element are in the compound. for $N$, it is 2. For $O$, it is 5.

$14.0 g$ $O$ * 2 = $28.0 g$ $N$

$16.0 g$ $O$ * 5 = $80.0 g$ $O$

add the two weights together to get the total weight of ${N}_{2} {O}_{5}$

$28.0 g$ + $80.0 g$ = $108 g$ ${N}_{2} {O}_{5}$

Divide each elements weight by the total weight of the compound and multiply by 100 and you will have the percentage composition

$\frac{28.0 g N}{108 g}$ * 100 = 25.93% $N$

$\frac{80.0 g O}{108 g}$ * 100 = 74.07% $O$