[bblue]

The standard reduction potential for the half-reaction

Sn4+ + 2e- --> Sn2+
is +0.15 V.

Consider data from the table of standard reduction potentials for common half-reactions, in your text.
For a galvanic cell under standard conditions, which of the following cathodic half reactions would produce, at the anode, a spontaneous oxidation of Sn to Sn2+ but not Sn2+ to Sn4+.

2H+ + 2e- --> H2         
Pb2+ + 2e- --> Pb
Cu2+ + e- --> Cu+
Sn4+ + 2e- --> Sn2+
Fe2+ + 2e- --> Fe
Sn2+ + 2e- --> Sn

This was my ans to the above qn, and i got this wrong:
yes
yes
no
yes
no
yes

and i also tried this and got it wrong
yes
no
no
yes
no
yes

Can someone please help me???