Question

Which statement is true in regard to a spontaneous redox reaction?

• A. $\text{E}_{\text{red}}^{}$ is always negative
• B. $E_{cell}^{}$ is always positive
• C. $E_{ox}^{}$ is always positive
• D. $E_{red}^{}$ is always positive

Answer 1

Answer: (B)

A spontaneous process is one that occurs on its own, without any energy input from the outside. $\Delta G=-ve$ for spontaneous redox reactions.
$ΔG=-nFE_{cell}^{}$
If $E_{cell}^{}$ is +ve, then $ΔG^{}$ will be –ve showing that cell reaction is spontaneous.