At 298 K, the standard reduction potential for the Cu2+/Cu electrode is 0.34 V.
Given: KspCu(OH)2=1×10-20
Take 2.303RTF=0.059 V
The reduction potential at pH = 14 for the above couple is (-)x×10-2V. The value of x is __________ . [2023]
(25)
pH=14⇒pOH=0
[OH-]=1
KspCu(OH)2=[Cu2+][OH-]2=1×10-20
[Cu2+]=10-20
ECu2+|Cu=ECu2+|Cu0-0.0592log1[Cu2+]
=0.34-0.0592log1020
= -0.25
=-25×10-2 V