# How do you calculate the percentage composition of Copper in CuSO_4?

$\text{Molar mass of copper"/"Molar mass of copper sulfate}$ xx100%
$\frac{63.55 \cdot g \cdot m o {l}^{-} 1}{\left(63.55 + 32.06 + 4 \times 15.999\right) \cdot g \cdot m o {l}^{-} 1}$ xx100% $=$ ?%
Note that the anhydrous salt is white, but it dissolves in water to give a beautiful blue solution, due to the ${\left[C u {\left(O {H}_{2}\right)}_{6}\right]}^{2 +}$ complex.