Q.

Consider the following reduction processes:

Al3++3e-⟶Al(s),    E°=-1.66 V 

Fe3++e-⟶Fe2+,    E°=+0.77 V

Co3++e-⟶Co2+,    E°=+1.81 V

Cr3++3e-⟶Cr(s),    E°=-0.74 V

The tendency to act as reducing agent decreases in the order:              [2026]

1 Al>Fe2+>Cr>Co2+  
2 Al>Cr>Co2+>Fe2+  
3 Cr>Fe2+>Al>Co2+  
4 Al>Cr>Fe2+>Co2+  

Ans.

(4)

Reducing power∝1Reduction potential