Question

Two half-cells have potentials $-0.44$ and $0.799$ volt respectively. These two are coupled to make a galvanic cell. Which of the following will be true?

• A. Electrode of half-cell potential $-0.44V$ will act as anode
• B. Electrode of half-cell potential $0.799V$ will act as anode
• C. Electrode of half-cell potential $-0.44V$ will act as cathode
• D. Electrode of half-cell potential $-0.44V$ will act as a positive terminal

Answer 1

Answer: (A)

Galvanic Cell:-

$\to$ In Galvanic cell,left hand side (anode), oxidation occurs. At right hand side electrode(cathode) , reduction occurs.

$\to$ The sum of the oxidation half reaction at anode and reduction half reaction at cathode is the overall cell reaction.

$\to$ Electrode with positive value of electrode potential suggest forward reaction i.e. reduction at cathode. So, electrode with 0.799 volt will act as cathode.

$\to$Electrode with negative value of electrode potential suggest reverse reaction i.e. oxidation at anode. Hence, electrode with -0.44 volt will act as anode.