I was given this problem in Mastering Chemistry: \" Which of the following redox

Question

I was given this problem in Mastering Chemistry:

" Which of the following redox reactions do you expect to occur spontaneously in the forward direction?

Fe2+(aq)+Zn(s)Fe(s)+Zn2+(aq) Cr(s)+3Ag+(aq)Cr3+(aq)+3Ag(s) " So I know from a previous Chegg answer that I would have to use a table of electrode values to determine if Ecell is positive (spontaneous) or negative (nonspontaneous). But what if they ask me "Will any of these reactions be spontaneous in the reverse direction?" Would I just multiply the given values in the table by -1 and proceed to use Ecell= Ered(cathode)-Ered(anode)?

Explanation / Answer

When a chemical reaction reaches equilibrium it is a reversible reaction. This is because in the balance, reagents produce substances, and these substances are able to regenerate the reagents. Reaction speeds to the right and to the left of the reaction will be the same.

Now, if these reactions are spontaneous in reverse, the only change in the formula above is the sign of Ecell. If the reaction goes from left to right (reagent to products) it is POSITIVE, and if the reaction goes from right to left (reactive to products) is NEGATIVE.

For example: If the reduction occurs at the anode, and the oxidation occurs at the cathode, It's better for you to change the labels on the electrodes.

I hope I was clear with this explanation. Please, make any comment about. We are here to help you

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

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