Question

For the electrochemical cell pictured below, determine if the system is spontaneous at ${25}^{\circ }C$:
Note: $C{u}_{\left(aq\right)}^{2+}+2e^{-}\to C{u}_{\left(s\right)}{E}^{\circ }=0.337V$
$Z{n}_{\left(aq\right)}^{2+}+2e^{-}\to Z{n}_{\left(s\right)}{E}^{\circ }=-0.763V$

• A. $△G^{\circ }=-212kJ$
  The reaction is spontaneous.
• B. $△G^{\circ }=-212kJ$
  The reaction is not spontaneous.
• C. $△G^{\circ }=+212kJ$
  The reaction is spontaneous.
• D. $△G^{\circ }=+212kJ$
  The reaction is not spontaneous.

Answer 1

The correct option is A $△G^{\circ }=-212kJ$

The reaction is spontaneous.
$E^0$ of $Zn=-0.763$

$E^0$ of $Cu=0.337$

$E_{cell}^0$ = $0.337-(-0.763)V=1.1V$

$\Delta G^0=-nF{E}_{cell}^0$

$\Delta G^0$ = $-2\ast 96500\ast 1.1$

$\Delta G^0$ = $-212kJ$ and process is spontaneous.