# What is the percentage composition by mass of the constituent atoms in calcium nitrate?

Feb 2, 2017

%Ca=24.4%................"by mass"

#### Explanation:

$\text{Calcium nitrate has a molar mass of } 164.09 \cdot g \cdot m o {l}^{-} 1$. We take the weighted atomic masses of each element, and divide them by this molar mass:

%Ca $=$ (40.1*g*mol^-1)/(164.09*g*mol^-1)xx100%=24.4%

%N $=$ (2xx14.01*g*mol^-1)/(164.09*g*mol^-1)xx100%=17.1.%

%O $=$ (6xx16.00*g*mol^-1)/(164.09*g*mol^-1)xx100%=58.5%

Should the individual atomic percentages SUM to 100%? Well, does they?