无机化学电极电势的计算····
问题描述:
无机化学电极电势的计算····
按E cu2/+cu+计算为0.867
答
E0(Cu2+/Cu)=0.337v
显然E0(Cu2+/Cu+)=0.159v
Cu2+ +e- +I-=CuI
1mol/L1mol/L
它的本质:
Cu2+ +e- =Cu+
1mol/LKsp/1mol/L
E0(Cu2+/CuI)=E(Cu2+/Cu+)
=E0(Cu2+/Cu+)+0.0591v*lg[Cu2+]/[Cu+]
=E0(Cu2+/Cu+)+0.0591v*lg1/KspCuI
=0.159v +0.0591V*lg[1/(1.1*10^-12)]
=0.866v
因此:
正极:Cu2+ +e- +I-=CuIE0(Cu2+/CuI)=0.866v
负极:I2 = 2e-=2I- E0(I2/I-)=0.535v
电动势=0.866V-0.535V =0.331v>0
瓜完全进行
即 2Cu2+ + 4I-=2CuI +I2