a) You have previously used KMNO 4 in acid solution as a strong oxidizing agent

Question

a) You have previously used KMNO4 in acid solution as a strong oxidizing agent and SnCl2 as a good reducing agent. Diagram a galvanic cell involving these two reagents. Clearly indicate (1) your choice of electrodes (2) ions in the solutions, and (3) the behaviour of all parts of the cell in detail, as you did for the Daniell cell.

b) Write the net ionic equations for each electrode reaction and for the total cell reaction.

c) Calculate the potential to be expected if all ions are at 1 M concentration

d) If the MnO4- concentration is increased, the cell voltage will ______

If the Sn4+ concentration is increased, the cell voltage will ______

Please help, I'll give a thumbs up.

Explanation / Answer

a)

the oxidation occurs in the anode (Sn will form Sn+4)

reduction occurs in the cathode (Mn reduces from +7 to +2)

b)

net ionic equations

MnO4 + 2 H2O + 3 e MnO2(s) + 4 OH 1.692

Sn2+ Sn4+ + 2 e E = -0.15

c)

E°cell = Ered + Eox = 1.692-0.15 = 1.542V

d)

if we increase MnO4- --> this favours increase in Ecell value

if Sn+4 increases ( a product) --> this favours backward reaciton, so Ecell reduces

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