Question

what is the action concentrated sulphuric acid on Zn,Mg,Fe,Cu,H2S

Answer 1

Magnesium ion and zinc their displace hydrogen from H2 s o4 but copper does not remove hydrogen from H2 s o4 and H2S does not react with H2 s o4

Answer 2

Usually metals react with acid to release the hydrogen gas.

There are many metals which react with concentrated acid to release $\mathrm{H}_{2}$ gas and form the metallic salt such as:

$\bold{\mathrm{Zn}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow \mathrm{ZnSO}_{4}+\mathrm{H}_{2}}$

$\bold{\mathrm{Mg}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow \mathrm{MgSO}_{4}+\mathrm{H}_{2}}$

$\bold{3 \mathrm{Fe}+8 \mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow \mathrm{FeSO}_{4}+\mathrm{Fe}_{2}\left(\mathrm{SO}_{4}\right)_{3}+4 \mathrm{SO}_{2}+8 \mathrm{H}_{2} \mathrm{O}}$

$\bold{2 \mathrm{H}_{2} \mathrm{SO}_{4}+\mathrm{Cu}(\mathrm{s}) \rightarrow \mathrm{CuSO}_{4}+\mathrm{SO}_{2}+2 \mathrm{H}_{2} \mathrm{O}}$

$\bold{\mathrm{H}_{2} \mathrm{S}+\mathrm{H}_{2} \mathrm{SO}_{4} \rightarrow \mathrm{S}+\mathrm{SO}_{2}+2 \mathrm{H}_{2} \mathrm{O}}$

Zn and Mg forms sulphate with $\bold{\mathrm{H}_{2}}$ gas whereas Fe and Cu also produce Sulphur dioxide and water. Hydrogen sulfide react with sulfuric acid to form sulfur, sulfur dioxide and water.