Question

Which reaction occurs at the anode of a galvanic cell that has a zinc

electrode in an electrolyte with zinc ions and a copper electrode in an
electrolyte with copper ions? The reduction potential for the reduction of Cu2+
= 0.34 V. The reduction potential for the reduction of Zn2+ = -0.76 V.
A. Zn(s) → Zn2+(aq) + 2e
B. Cu(s) → Cu2+(aq) + 2e
C. Zn2+ (aq) + 2e → Zn(s)
D. Cu2+ (aq) + 2e →
Cu(s)

Answer 1

Answer: The reaction that occurs at anode is
`Zn(s)\rightarrow Zn^(2+)(aq.)+2e^-`

Step-by-step explanation:

Given :
`E^o_(Zn^(2+)/Zn)=-0.76V`

`E^o_(Cu^(2+)/Cu)=+0.34V`

The substance having highest positive reduction potential will always get reduced and will undergo reduction reaction. Here, copper will undergo reduction reaction will get reduced.

The substance having highest negative reduction potential will always get oxidised and will undergo oxidation reaction. Here, zinc will undergo oxidation reaction will get oxidised.

Oxidation reaction occurs at anode and reduction reaction occurs at cathode.

Oxidation half reaction (anode) :
`Zn(s)\rightarrow Zn^(2+)(aq.)+2e^-`

Reduction half reaction (cathode) :
`Cu^(2+)(aq.)+2e^-\rightarrow Cu(s)`