Question

9.
What happens when
(a) Dilute sulphuric acid is poured on a copper plate?
(b) Iron nails are placed in copper sulphate solution?
Write word equations of the reactions involved.
the sas evolve​

Answer 1

a) Copper does not react with dilute sulphuric acid. So, no reaction takes place when dilute sulphuric acid is poured on a copper plate. But when concentrated sulphuric acid is poured over copper plate, effervescence is observed. This happens because of formation of hydrogen gas.

Cu + H2SO4 → CuSO4 + H2

b) When an iron nail is dipped in copper sulphate solution, a brown coating of copper is formed on the surface of iron and the colour of copper sulphate solution changes from blue to light green.

CuSO4 + Fe → FeSO4 + Cu