# How can I find the percent compositions of N2S2?

May 28, 2014

To find the percent composition of N₂S₂, you divide the total mass of each atom by the molecular mass and multiply by 100 %.

% by mass = $\text{mass of component"/"total mass}$ × 100 %

Mass of 2 N atoms = 2 N atoms × $\left(14.01 \text{u")/(1"N atom}\right)$ = 28.02 u.

Mass of 2 S atoms = 2 S atoms × $\left(32.06 \text{u")/(1"S atom}\right)$ = 64.12 u

Mass of 1 N₂S₂ molecule = (28.02 + 64.12) u = 92.14 u

% of N = $\text{mass of N"/"total mass}$ × 100 % = $\left(28.02 \text{u")/(92.14"u}\right)$ × 100 % =30.41 %

% of S = $\text{mass of S"/"total mass}$ × 100 % = $\left(64.12 \text{u")/(92.14"u}\right)$ × 100 % =69.59 %