The metal from the first transition series having positive \(E_{M^{2+}/M}^0\) value:
Answer & explanation
Correct answer: option 3
In the electrochemical series, Cu is below hydrogen.
Hence, it has a positive value of standard reduction potential \(E_{M^{2+}/M}^0\).
The standard reduction potentials are given below:
Cr (Z = 24) = − 0.91 V
V (Z= 23) = −1.18 V
Cu (Z=29) = +0.34 V
Ni (Z= 30) = −0.76 V