# How do you calculate the percentage of Cu in CuSO_4? What is the atomic weight (mass) of each element?

Dec 15, 2016

$\text{% element}$ $=$ "Mass of element"/"Formula mass of compound"xx100%

#### Explanation:

%Cu $=$ (63.55*g*mol^-1)/(159.61*g*mol^-1)xx100%=39.8%

%S $=$ (32.06*g*mol^-1)/(159.61*g*mol^-1)xx100%=??%

%O $=$ (4xx15.999*g*mol^-1)/(159.61*g*mol^-1)xx100%=??%.

Should the elemental percentages sum to 100%. Why?