# A compound is broken down into 34.5 g of element A, 18.2 g of element B, and 2.6 g of element C. What is the percent (by mass) of each element?

Oct 10, 2016

A=62.3%,B=33.0%,C=4.70%.

#### Explanation:

%A $=$ (34.5*g)/(34.5*g+18.2*g+2.6*g)xx100%=62.3%

%B $=$ (18.2*g)/(34.5*g+18.2*g+2.6*g)xx100%=33.0%

%C $=$ (2.6*g)/(34.5*g+18.2*g+2.6*g)xx100%=4.70%

That is %" element" $=$ "Mass of element"/"Mass of compound"xx100%

$\text{Mass of compound}$ is clearly the SUM of the constituent elements.