Question

The standard electrode potential for the reduction of Eu3+(aq) to Eu2+(aq) is −0.43 V. determine which of the following is capable of reducing Eu3+(aq) to Eu2+(aq) under standard-state conditions?


(a) Sn2+(aq)
(b) ln(s)
(c) HCN(aq)
(d) La(s)

Answer 1

We really prefer that you not switch screen names. We can keep up better and answer faster if you use the same name for each post.
Eu^3+ + e ==> Eu^2+
Sn^2+ ==> Sn^4+ + 2e
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You have Eo for Eu3+ to Eu^2+.
Look up Sn^4+ to Sn^2+, change the sign, and add to the Eu couple. If the resulting E value is + that material (Sn2+ in this case) will reduce the Eu 3+ to 2+. If negative, no.
b,c,d, are done the same way.

Answer 2

Yes

Answer 3

thanks you