`{:(E_(M^(2+)//M)^(@),Cr,Mn, Fe, Co, Ni, Cu),(,-0.91,-1.18,-0.44,-0.28,-0.25,+0.34):}` From the given data of `E^(@)` values, answer the following questions : (i) Why is `E_((Cu^(2+)//Cu))^(@)` value exceptionally positive ? (ii) Why is `E_((M^(2+)//M))^(@)` vlue highly negative as compared to other elements ? (iii) Which is a stronger reducing agent , `Cr^(2+)` or `Fe^(2+)` ? Give reason.

`{:(E_(M^(2+)//M)^(@),Cr,Mn, Fe, Co, Ni, Cu),(,-0.91,-1.18,-0.44,-0.28

1.	`{:(E_(M^(2+)//M)^(@),Cr,Mn, Fe, Co, Ni, Cu),(,-0.91,-1.18,-0.44,-0.28,-0.25,+0.34):}` From the given data of `E^(@)` values, answer the following questions : (i) Why is `E_((Cu^(2+)//Cu))^(@)` value exceptionally positive ? (ii) Why is `E_((M^(2+)//M))^(@)` vlue highly negative as compared to other elements ? (iii) Which is a stronger reducing agent , `Cr^(2+)` or `Fe^(2+)` ? Give reason.
Answer» (i) This is due to the reason that `Cu^(2+)` ion has high value of `Delta_(a)H^(@)` and low `Delta_(hy)H^(@)`. (ii) This is due to the reason that `Mn^(2+)(3d^(5))` configuration is exceptionally stable. (iii) `Cr^(2+)` is a stronger reducing agent because of +3 oxidation state of Cr ( `t_(2g)^(3)` orbital) is more stable.