An aqueous solution containing 1M each of `Au^(3+), Cu^(2+), Ag^(+), Li^(+)` is being electrolysed by using inert electrodes. The value of standard potentials are
`E_(Ag^(+)//Ag)^(@)= 0.80V, E_(Cu^(2+)//Cu)^(@) = 0.34V, and E_(Au^(3+)//Au)^(@) = 1.50 V`,
`E_(Li^(+)//Li)^(@)= -3.03V`, With increasing voltage, the sequence of deposition of metals on the cathode will be

Options

A. Li, Cu, Ag, Au
B. Cu, Ag, Au
C. Au, Ag, Cu
D. Au, Ag, Cu, Li

Answer

C

Explanation

Only `Au^(3+), Ag^(+) and Cu^(2+)` will deposit at cathode. Li will not deposit at cathode because SRP of water is `0.8274V` so after `Cu^(2+), H_(2)` will evolve at cathode.