# Does "copper(II) sulfate" contain both ionic and covalent bonds?

Jul 17, 2017

I presume you mean to ask why $C u S {O}_{4}$ has both covalent and ionic bonds........if no, I apologize.
$C u S {O}_{4} \left(s\right)$ is a white solid, that is composed of $C {u}^{2 +}$, and $S {O}_{4}^{2 -}$ ions, bound together by strong electrostatic forces that exist between oppositely charged ions. $S {O}_{4}^{2 -}$ is a charged species, an ion that we could represent as ${\left(O =\right)}_{2} S {\left(- {O}^{-}\right)}_{2}$ (of course all the oxygen atoms are equivalent). With me?
Within the sulfate ion, there is a strong degree of covalency. The overall charge on this covalently bound species is $- 2$; and hence is forms a salt with $C {u}^{2 +}$ to give the required $C u S {O}_{4}$.
Place WHITE $C u S {O}_{4}$ in water, and you see the colour change to give a beautiful blue due to ${\left[C u {\left(O {H}_{2}\right)}_{6}\right]}^{2 +}$ or a variant. The beautiful crystals that you see in the diagram are due to ${\left[C u {\left(O {H}_{2}\right)}_{5}\right]}^{2 +} S {O}_{4}^{2 -} \cdot {H}_{2} O$, so-called $\text{blue vitriol}$.