Examine the following half-reactions and select the strongest reducing agent among the species listed.
HgO(s) + H₂O(l) + 2e^-
Hg(l) + 2OH^-(aq) ;E° = 0.0977 V
Zn(OH) ₂(s) + 2e^-
Zn(s) + 2OH^-(aq) ;E° = -1.25 V
Ag₂O(s) + H₂O(l) + 2e^-
Ag(s) + 2OH^-(aq) ;E° = 0.342 V
B(OH) ₃(aq) + 7H⁺(aq) + 8e^-
BH₄^-(aq) + 3H₂O(l) ;E° = -0.481 V

Question

Examine the following half-reactions and select the strongest reducing agent among the species listed.
HgO(s) + H₂O(l) + 2e^-

Examine the following half-reactions and select the strongest reducing agent among the species listed. HgO(s) + H<sub>2</sub>O(l) + 2e<sup>-</sup> Hg(l) + 2OH<sup>-</sup>(aq) ;E° = 0.0977 V Zn(OH) <sub>2</sub>(s) + 2e<sup>-</sup> Zn(s) + 2OH<sup>-</sup>(aq) ;E° = -1.25 V Ag<sub>2</sub>O(s) + H<sub>2</sub>O(l) + 2e<sup>-</sup> Ag(s) + 2OH<sup>-</sup>(aq) ;E° = 0.342 V B(OH) <sub>3</sub>(aq) + 7H<sup>+</sup>(aq) + 8e<sup>-</sup> BH<sub>4</sub><sup>-</sup>(aq) + 3H<sub>2</sub>O(l) ;E° = -0.481 V A) Hg(l) B) Zn(s) C) Ag(s) D) BH<sub>4</sub><sup>-</sup>(aq) E) Zn(OH) <sub>2</sub>(s)

Hg(l) + 2OH^-(aq) ;E° = 0.0977 V
Zn(OH) ₂(s) + 2e^-

Zn(s) + 2OH^-(aq) ;E° = -1.25 V
Ag₂O(s) + H₂O(l) + 2e^-

Ag(s) + 2OH^-(aq) ;E° = 0.342 V
B(OH) ₃(aq) + 7H⁺(aq) + 8e^-

BH₄^-(aq) + 3H₂O(l) ;E° = -0.481 V

Quizplus · Accepted Answer

The stronger the reducing agent, the more easily it gives away electrons. The lower the standard reduction potential (E°) of a half-reaction, the stronger the reducing agent is. From the given half-reactions, we can see that the standard reduction potential of the Zn/Zn(OH)2 half-reaction is the lowest at -1.25 V, indicating that it is the strongest reducing agent among the given species. Therefore, the answer is B, Zn(s).

Examine the Following Half-Reactions and Select the Strongest Reducing Agent