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If E(A^(+2)//A)^(@)=-0.30 V and E(A^(+3)...

If `E_(A^(+2)//A)^(@)=-0.30 V and E_(A^(+3)//A^(+2))^(@)=0.40 V,` the standard Emf of the reaction: `A+2A^(+3)to3A^(+2)` will be :-

A

0.30 V

B

0. 40 V

C

0. 70 V

D

0. 10 V

Text Solution

Verified by Experts

The correct Answer is:
C
Anode reaction `AtoA^(+2)+2e^(-)`
cathode reaction `2A^(+3)+2e^(-)to2A^(+2)`
`E_(ceel)^(@)=E_(cathode)^(@)-E_(Anode)^(@)`
`=0.4-(-0.3)`
0.7 V
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