Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 20: Problem 112

For the half-reaction \(\mathrm{Hg}^{2+}(\mathrm{aq})+2 \mathrm{e}^{-} \longrightarrow \mathrm{Hg}(1)\) \(E^{\circ}=0.854 \mathrm{V} .\) This means that \((\mathrm{a}) \mathrm{Hg}(1)\) is more readily oxidized than \(\mathrm{H}_{2}(\mathrm{g}) ;\) (b) \(\mathrm{Hg}^{2+}(\) aq) is more readily reduced than \(\mathrm{H}^{+}(\mathrm{aq}) ;\) (c) \(\mathrm{Hg}(\) l) will dissolve in 1 M HCl; (d) Hg(l) will displace Zn(s) from an aqueous solution of \(\mathrm{Zn}^{2+}\) ion.

Short Answer

Expert verified
(a) True, (b) True, (c) False, (d) True.

Step by step solution

01

Check if Hg(l) is more readily oxidized than H2(g)

The standard cell potential of hydrogen (E0_H2) is defined as 0V so it is less than the standard reduction potential of Hg^2+ which is 0.854V, meaning at standard conditions, Hg(l) is oxidized (loses electrons) more readily than Hg(g). So (a) is True.
02

Check if Hg^2+(aq) is more readily reduced than H+(aq)

The standard reduction potential of H+ (E0_H+) is 0V which is less than the standard reduction potential of Hg^2+ (E0_Hg) which is 0.854V, meaning at standard conditions, Hg^2+(aq) is reduced more readily than H+(aq). So (b) is True.
03

Check if Hg(l) will dissolve in 1 M HCl

Hg(l) won't dissolve in 1M HCl because Hg(l) is not easily oxidized by H+ ions whose (E0_H+) is 0V which less than the standard reduction potential of Hg^2+ (E0_Hg) which is 0.854V. So (c) is False.
04

Check if Hg(l) will displace Zn(s) from an aqueous solution of Zn^2+ ion

The standard reduction potential for Zn^2+/Zn (E0_Zn) is -0.76V which is less than the standard reduction potentials of Hg^2+/Hg (i.e., 0.854V). Thus, Hg(l) can displace Zn(s) from a solution of Zn^2+ ions since it has a higher reduction potential. So (d) is True.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Consider two cells involving two metals \(X\) and \(Y\) $$\begin{aligned} \mathrm{X}(\mathrm{s})\left|\mathrm{X}^{+}(\mathrm{aq})\right|\left|\mathrm{H}^{+}(\mathrm{aq}), \mathrm{H}_{2}(\mathrm{g}, 1 \mathrm{bar})\right| \mathrm{Pt}(\mathrm{s}) & \\\ \mathrm{X}(\mathrm{s})\left|\mathrm{X}^{+}(\mathrm{aq}) \| \mathrm{Y}^{2+}(\mathrm{aq})\right| \mathrm{Y}(\mathrm{s}) \end{aligned}$$ In the first cell electrons flow from the metal \(X\) to the standard hydrogen electrode. In the second cell electrons flow from metal \(X\) to metal Y. Is \(E_{x^{+} / x}^{\circ_{+}}\) greater orless than zero? Is \(E_{x^{+} / x}^{\circ}>E_{\mathrm{Y}^{2+}},_{\mathrm{Y}} ?\) Explain.

Show that for nonstandard conditions the temperature variation of a cell potential is $$E\left(T_{1}\right)-E\left(T_{2}\right)=\left(T_{1}-T_{2}\right) \frac{\left(\Delta S^{\circ}-R \ln Q\right)}{z F}$$ where \(E\left(T_{1}\right)\) and \(E\left(T_{2}\right)\) are the cell potentials at \(T_{1}\) and \(T_{2},\) respectively. We have assumed that the value of \(Q\) is maintained at a constant value. For the nonstandard cell below, the potential drops from \(0.394 \mathrm{V}\) at \(50.0^{\circ} \mathrm{C}\) to \(0.370 \mathrm{V}\) at \(25.0^{\circ} \mathrm{C} .\) Calculate \(Q\) \(\Delta H^{\circ},\) and \(\Delta S^{\circ}\) for the reaction, and calculate \(K\) for the two temperatures. $$\mathrm{Cu}(\mathrm{s})\left|\mathrm{Cu}^{2+}(\mathrm{aq}) \| \mathrm{Fe}^{3+}(\mathrm{aq}), \mathrm{Fe}^{2+}(\mathrm{aq})\right| \mathrm{Pt}(\mathrm{s})$$ Choose concentrations of the species involved in the cell reaction that give the value of \(Q\) that you have calculated, and then determine the equilibrium concentrations of the species at \(50.0^{\circ} \mathrm{C}\)

In the construction of the Statue of Liberty, a framework of iron ribs was covered with thin sheets of copper less than \(2.5 \mathrm{mm}\) thick. A layer of asbestos separated the copper skin and iron framework. Over time, the asbestos wore away and the iron ribs corroded. Some of the ribs lost more than half their mass in the 100 years before the statue was restored. At the same time, the copper skin lost only about \(4 \%\) of its thickness. Use electrochemical principles to explain these observations.

From the observations listed, estimate the value of \(E^{\circ}\) for the half- reaction \(\mathrm{M}^{2+}(\mathrm{aq})+2 \mathrm{e}^{-} \longrightarrow \mathrm{M}(\mathrm{s})\) (a) The metal M reacts with HNO \(_{3}(\text { aq })\), but not with \(\mathrm{HCl}(\mathrm{aq}) ; \mathrm{M}\) displaces \(\mathrm{Ag}^{+}(\mathrm{aq}),\) but not \(\mathrm{Cu}^{2+}(\mathrm{aq})\) (b) The metal \(M\) reacts with \(\mathrm{HCl}(\mathrm{aq}),\) producing \(\mathrm{H}_{2}(\mathrm{g}),\) but displaces neither \(\mathrm{Zn}^{2+}(\text { aq })\) nor \(\mathrm{Fe}^{2+}(\mathrm{aq})\).

Derive a balanced equation for the reaction occurring in the cell: $$\mathrm{Fe}(\mathrm{s})\left|\mathrm{Fe}^{2+}(\mathrm{aq}) \| \mathrm{Fe}^{3+}(\mathrm{aq}), \mathrm{Fe}^{2+}(\mathrm{aq})\right| \mathrm{Pt}(\mathrm{s})$$ (a) If \(E_{\text {cell }}^{\circ}=1.21 \mathrm{V},\) calculate \(\Delta G^{\circ}\) and the equilibrium constant for the reaction. (b) Use the Nernst equation to determine the potential for the cell: $$\begin{array}{r} \mathrm{Fe}(\mathrm{s}) | \mathrm{Fe}^{2+}\left(\mathrm{aq}, 1.0 \times 10^{-3} \mathrm{M}\right) \| \mathrm{Fe}^{3+}\left(\mathrm{aq}, 1.0 \times 10^{-3} \mathrm{M}\right) \\ \mathrm{Fe}^{2+}(\mathrm{aq}, 0.10 \mathrm{M}) | \mathrm{Pt}(\mathrm{s}) \end{array}$$ (c) In light of (a) and (b), what is the likelihood of being able to observe the disproportionation of \(\mathrm{Fe}^{2+}\) into \(\mathrm{Fe}^{3+}\) and Fe under standard conditions?
See all solutions

Recommended explanations on Chemistry Textbooks

Ionic and Molecular Compounds

Read Explanation

Inorganic Chemistry

Read Explanation

Physical Chemistry

Read Explanation

Chemical Analysis

Read Explanation

Chemistry Branches

Read Explanation

Making Measurements

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free