Question

A metal X displaces nickel from nickel sulphate solution but does not displace manganese from manganese sulphate solution. What is the correct order of their reducing powers?

• A. Ni > Mn > X
• B. X > Mn > Ni
• C. Mn > X > Ni
• D. Mn > Ni > X

Answer 1

Answer: (C)

Mn > X > Ni

Answer 2

: Since X displaces Ni from $NiSO_{4}$solution, it means X has higher oxidation potential or lower reduction potential than $Ni^{2 +}$ Since X cannot displace Mn from $MnSO_{4}$solution, it means it has higher reduction potential than $Mn^{2 +}$ Lower the reduction potential stronger is the reducing agent hence reducing power Mn > X > Ni.