Question

Explain how anhydrous Copper sulphate can be used in the detection of water.

Answer 1

Detection of Water:

• Anhydrous copper sulphate is a white coloured powder, which turns blue when it comes in contact with water.
• The colour change on adding water to anhydrous Copper sulphate(${\mathrm{CuSO}}_4$) has been used as test for the presence of water in a liquid.
• The appearance of a blue color in anhydrous Copper sulphate indicates the presence of moisture or water in the liquid.
• The balanced chemical reaction can be represented as:

$$\begin{gathered} {\mathrm{CuSO}}_4\left(\mathrm{s}\right)+5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to {\mathrm{CuSO}}_4.5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{s}\right) \\ (\mathrm{Anhydrous}\mathrm{Copper}\mathrm{sulphate})\left(\mathrm{Water}\right)(\mathrm{Hydrated}\mathrm{Copper}\mathrm{sulphate}) \end{gathered}$$

This is how anhydrous Copper sulphate can be used in the detection of water.