Consider a galvanic cell in which Al 3 is reduced to elemental aluminum and magnesium metal is oxidized to Mg 2 . Write the balanced half-cell reactions that take place at the cathode and at the anode.

The half cell reactions taking place at cathode and anode is written below.

Explanation:

Oxidation reaction occurs at anode and reduction reaction occurs at cathode. Here, magnesium is getting oxidized and aluminium is getting reduced.

The half reactions for the cell is:

Oxidation half reaction (anode):     ( ×  3)

Reduction half reaction (cathode):       ( ×  2)

Overall cell reaction:  

Hence, the half cell reactions taking place at cathode and anode is written above.

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