Given the potentials listed the standard redox Table 11.1, analyze the following

Question

Given the potentials listed the standard redox Table 11.1, analyze the following scenario. Chromium(III) (ie, Cr in the +3 oxidation state; Cr3+) converts to chromium metal (Cr0) at a potential of –0.73 V. Chromium(III) also converts to Cr2+ at a potential of –0.50 V. What do you think would happen if a reductant with a potential more negative than both, e.g, Zn0 (E0= –0.76 V), were added to a solution of Cr3+? Would some of it convert to Cr2+, while the rest converted to Cr0? Here is a link to redox potential table: https://sites.google.com/a/ramapocentral.net/ap-chemistry/chapter-17-electrochemistry/standard-reduction-potentials

Explanation / Answer

Cr3+ + 3 e Cr(s) 0.73

Cr3+ + e Cr2+ 0.50

Cr2+(aq) + 2e- Cr(s) -0.91

If we add Zn(s) to solution

then expect Zinc to

Cr+3(aq) and Zn(s) remains

Cr+2(aq) and Zn(s) will not reduce

only

2Cr+3 + Zn(s) --> 2Cr+3(aq) + Zn+2(aq)

Related Questions

Navigate

• Browse (All)
• Browse G
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.