Give the principle to prepare H2S. Mention its reaction with an aqueous solution of CuSO4.
In the laboratory, H2S is prepared by the action of dilute sulphuric acid with ferrous sulphide at room temperature.
Equation : FeS + H2SO4 → FeSO4 + H2S
When hydrogen sulfide (H2S) reacts with an aqueous solution of CuSO4 (copper sulfate), it forms a precipitate of CuS (copper sulfide) and sulfuric acid (H2SO4) is also produced as a by-product. The balanced chemical equation for this reaction is:
H2S (g) + CuSO4 (aq) → CuS (s)↓ + H2SO4 (aq)