An electrochemical cell is made by connecting Nickel and Chromium electrodes. With the help of information given below, the correct value of standard cell potential, would be:

\(Ni^{2+} + 2e^- \longrightarrow Ni(s)\, \ E^o = -0.25V\)

\(Cr^{3+} + 3e^- \longrightarrow Cr(s)\, \ E^o = -0.74 V\)

+0.49 V

The correct answer is option 1. +0.49 V.

To find the standard cell potential (\(E^\circ_{cell}\)) of the electrochemical cell formed by the Nickel and Chromium electrodes, you can use the formula:

\(E^\circ_{cell} = E^\circ_{\text{cathode}} - E^\circ_{\text{anode}}\)

Given:

\(E^\circ_{\text{cathode}} \) (Nickel) = -0.25 V

\(E^\circ_{\text{anode}} \) (Chromium) = -0.74 V

Substitute the values into the formula:

\(E^\circ_{cell} = (-0.25) - (-0.74) \)

\(E^\circ_{cell} = 0.49 \, V \)

The correct value of the standard cell potential is \( +0.49 \, V \), so the correct answer is option 1.