Question

Which of the following reactions cannot
occur?
1. Cu(s) + 2HCl(aq) → CuCl2(aq) + H2
II. 2Al(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2
III. Pb(s) + H2SO4(aq) → PbSO4(aq) + H
IV. Cu(s) + MgSO4(aq) → CuSO4(aq) +
Mg(s)
Only I and III
Only I and II
Only I and IV
Only II and IV​

Answer 1

Answer:

only I and IV can't occur

Explanation:

because Cu is less reactive than H

Cu is less reactive than Mg

Only reactive metal can displaces least reactive

but Cu in both the cases is least reactive...

therefore single displacement will not occur.