Ncert Exercises & Solutions

8.7: Which is a stronger reducing agent Cr $^{2 +}$ or Fe $^{2 +}$ and why?

The following reactions are involved when Cr

^{2 +}

and Fe

^{2 +}

act as reducing agents.

\to C r C r_{2 +} \to F e_{3 +}

E °_{c r^{3 +} / c r^{2 +}}

The value is −0.41 V and

E °_{F e^{3 +} / F e^{2 +}}

is +0.77 V. This means that Cr2+ can be easily oxidized to Cr

^{2 +}

, can be easily oxidized to

C r^{3 +}

but,

F e^{2 +}

does not grt oxidized to Fe

^{3 +}

easily. Therefore, Cr

^{2 +}

is a better reducing agent that Fe

^{3 +}