Question

Aluminium displaces hydrogen from acids but
copper does not. A galvanic cell prepared by
combining Cu /Cu²⁺ and Al/Al³⁺ has an e.m.f
of 2.0 V at 298°K. If the potential of copper
electrode is + 0.34 V, that of aluminium is
(a) + 1.66 (b) – 1.66
(c) + 2.34 (d) – 2.3 V

Answer 1

Heyaa♡♡

Correct option: (b) – 1.66

The given statement explains that Al is placed above Cu in E.C.S. hence it can reduce Cu from its salt solution (reduction). Thus Al acts as a reducing agent now, Given : electrode potential of copper

( E0 Cell ) = + 0.34 V

e.m.f of cell = 2 V

We know that,

emf of a galvanic cell ( E0cell ) = electrode potential of Cu (cathode) – electrode potential of Al (anode)

=> 2.0 = 0.34 – E0 Al

=> E0 Al = 0.34 – 2.00 = – 1.66 V

Hence, electrode potential of Al is – 1.66 V.

Option (b) is correct.

Hope it helped you.

Answer 2

Hello Friend..!!

The answer of u r question is..!!

Option.C

Thank you..!!