Question

The conversion of energy to energy takes place through redox reaction in a galvanic cell.

• A. thermal
• B. chemical
• C. electrical
• D. mechanical

Answer 1

Answer: (B), (C)

electrical

A galvanic cell is an electrochemical cell. It converts the chemical energy of a spontaneous redox reaction to electrical energy.

For example, in Zn - Cu galvanic cell following reactions are observed:
Oxidation: $\text{Zn(s})\to {\text{Zn}}^{+2}(\text{aq})+2e^{-}$
Reduction: ${\text{Cu}}^{+2}\left(\text{aq}\right)+2e^{-}\to \text{Cu}\left(\text{s}\right)$

The overall reaction is a redox reaction and can be written as:
$\text{Zn(s})+{\text{Cu}}^{+2}(\text{aq})\to {\text{Zn}}^{+2}(\text{aq})+\text{Cu}(\text{s})$

The transfer of electrons involved in this reaction causes the flow of electric current in the cell.