The standard potentials at `298 K` for the following halfreactions are as given ` Zn^(2+) + 2e underset(larr)(rarr) Zn E^o =- 0/ 762 V`. `2 H^+ + 2 Erarr H_2 (g) E^o = 0.000 V` `Cr^(3+) + 3e underset(larr)(rarr) Cr E^o =- 0.740 V` `Fe^(3+) 2e rarr Fe^(2+) E^o =0.772 V` Which of the following is the strongest reducing agent ?A. Zn (s)B. CrC. `H_(2) (g)`D. `Fe^(2+) (aq)`

The standard potentials at `298 K` for the following halfreactions are

1.	The standard potentials at `298 K` for the following halfreactions are as given ` Zn^(2+) + 2e underset(larr)(rarr) Zn E^o =- 0/ 762 V`. `2 H^+ + 2 Erarr H_2 (g) E^o = 0.000 V` `Cr^(3+) + 3e underset(larr)(rarr) Cr E^o =- 0.740 V` `Fe^(3+) 2e rarr Fe^(2+) E^o =0.772 V` Which of the following is the strongest reducing agent ?A. Zn (s)B. CrC. `H_(2) (g)`D. `Fe^(2+) (aq)`
Answer» Correct Answer - A More negative the standard potential least the reducion tendcy of the ion. The corresponding atom has largest oxidation tendency and thus is a sterong reducing agent. `Zn` is the strongest reucing afent.

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