How is the equation for ${\mathrm{CuSO}}_4+{\mathrm{H}}_2\mathrm{O}$determined?

Blue vitriol:

• The reaction between ${\mathrm{H}}_2\mathrm{O}$ and ${\mathrm{CuSO}}_4$ gives ${\mathrm{CuSO}}_4.5{\mathrm{H}}_2\mathrm{O}$ which is called blue vitriol.
• On dehydration of copper sulfate, the water molecule is lost resulting in the formation of copper sulfate monohydrate(${\mathrm{CuSO}}_4.{\mathrm{H}}_2\mathrm{O}$) which is bluish-white colour.
• $\underset{\mathrm{Copper}\mathrm{sulphate}}{{\mathrm{CuSO}}_4\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{\mathrm{Copper}\mathrm{sulphate}\mathrm{pentahydrate}}{{\mathrm{CuSO}}_4.5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{s}\right)}$
• It is used as battery electrolytes.
• It is also used as a herbicide and a fungicide.