What reaction will take place at the cathode and the anode when each of the following is electrolyzed? (Assume standard conditions.) a. \(1.0 M \mathrm{KF}\) solution b. \(1.0 \mathrm{M} \mathrm{CuCl}_{2}\) solution c. \(1.0 \mathrm{MgI}_{2}\) solution

Short Answer

Expert verified
In the electrolysis of the given solutions: a. \(1.0 M \mathrm{KF}\) solution: - Anode (oxidation): 2 \(\mathrm{F}^-\) (aq) → \(\mathrm{F}_{2}\) (g) + 4 e\(^-\) - Cathode (reduction): 2 H\(_{2}\)O (l) + 2 e\(^-\) → H\(_{2}\) (g) + 2 OH\(^-\) (aq) b. \(1.0 M \mathrm{CuCl}_{2}\) solution: - Anode (oxidation): 2 \(\mathrm{Cl}^-\) (aq) → \(\mathrm{Cl}_{2}\) (g) + 2 e\(^-\) - Cathode (reduction): \(\mathrm{Cu}^{2+}\) (aq) + 2 e\(^-\) → \(\mathrm{Cu}\) (s) c. \(1.0 M \mathrm{MgI}_{2}\) solution: - Anode (oxidation): 2 \(\mathrm{I}^-\) (aq) → \(\mathrm{I}_{2}\) (s) + 2 e\(^-\) - Cathode (reduction): 2 H\(_{2}\)O (l) + 2 e\(^-\) → H\(_{2}\) (g) + 2 OH\(^-\) (aq)

Step by step solution

01

Identify the Cathode and Anode Reactions for the \(1.0 M \mathrm{KF}\) Solution

For a \(1.0 M \mathrm{KF}\) solution, we have both \(\mathrm{K}^+\) ions and \(\mathrm{F}^-\) ions. The anode is where oxidation takes place while the cathode is where reduction takes place. At the anode (oxidation), the possible reactions include: -2 \(\mathrm{F}^-\) (aq) → \(\mathrm{F}_{2}\) (g) + 4 e\(^-\) At the cathode (reduction), the possible reactions include: - \(\mathrm{K}^+\) (aq) + e\(^-\) → \(\mathrm{K}\) (s) - 2 H\(_{2}\)O (l) + 2 e\(^-\) → H\(_{2}\) (g) + 2 OH\(^-\) (aq) Using standard reduction potentials, we can determine that fluorine has a higher reduction potential than water, so it will be easier for \(\mathrm{F}^-\) ions to be oxidized. Meanwhile, potassium's reduction potential is lower than that of water, so it will be harder to reduce \(\mathrm{K}^+\) ions compared to the reduction of water. So in the \(1.0 M \mathrm{KF}\) solution, the reactions are: Anode (oxidation): 2 \(\mathrm{F}^-\) (aq) → \(\mathrm{F}_{2}\) (g) + 4 e\(^-\) Cathode (reduction): 2 H\(_{2}\)O (l) + 2 e\(^-\) → H\(_{2}\) (g) + 2 OH\(^-\) (aq)
02

Identify the Cathode and Anode Reactions for the \(1.0 M \mathrm{CuCl}_{2}\) Solution

For a \(1.0 M \mathrm{CuCl}_{2}\) solution, we have both \(\mathrm{Cu}^{2+}\) ions and \(\mathrm{Cl}^-\) ions. As before, we must determine the reactions at the anode (oxidation) and cathode (reduction). At the anode (oxidation), the possible reactions include: - 2 \(\mathrm{Cl}^-\) (aq) → \(\mathrm{Cl}_{2}\) (g) + 2 e\(^-\) At the cathode (reduction), the possible reactions include: - \(\mathrm{Cu}^{2+}\) (aq) + 2 e\(^-\) → \(\mathrm{Cu}\) (s) The most likely reactions to occur are: Anode (oxidation): 2 \(\mathrm{Cl}^-\) (aq) → \(\mathrm{Cl}_{2}\) (g) + 2 e\(^-\) Cathode (reduction): \(\mathrm{Cu}^{2+}\) (aq) + 2 e\(^-\) → \(\mathrm{Cu}\) (s)
03

Identify the Cathode and Anode Reactions for the \(1.0 M \mathrm{MgI}_{2}\) Solution

For a \(1.0 M \mathrm{MgI}_{2}\) solution, we have both \(\mathrm{Mg}^{2+}\) ions and \(\mathrm{I}^-\) ions. Let's determine the reactions at the anode (oxidation) and the cathode (reduction). At the anode (oxidation), the possible reactions include: - 2 \(\mathrm{I}^-\) (aq) → \(\mathrm{I}_{2}\) (s) + 2 e\(^-\) At the cathode (reduction), the possible reactions include: - \(\mathrm{Mg}^{2+}\) (aq) + 2 e\(^-\) → \(\mathrm{Mg}\) (s) - 2 H\(_{2}\)O (l) + 2 e\(^-\) → H\(_{2}\) (g) + 2 OH\(^-\) (aq) Using standard reduction potentials, we can determine that magnesium's reduction potential is lower than that of water, so it will be harder to reduce \(\mathrm{Mg}^{2+}\) ions compared to the reduction of water. So in the \(1.0 M \mathrm{MgI}_{2}\) solution, the reactions are: Anode (oxidation): 2 \(\mathrm{I}^-\) (aq) → \(\mathrm{I}_{2}\) (s) + 2 e\(^-\) Cathode (reduction): 2 H\(_{2}\)O (l) + 2 e\(^-\) → H\(_{2}\) (g) + 2 OH\(^-\) (aq)

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.

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

Balance the following equations by the half-reaction method. a. \(\mathrm{Fe}(s)+\mathrm{HCl}(a q) \longrightarrow \mathrm{HFeCl}_{4}(a q)+\mathrm{H}_{2}(g)\) b. \(\mathrm{IO}_{3}^{-}(a q)+\mathrm{I}^{-}(a q) \stackrel{\text { Acid }}{\longrightarrow} \mathrm{I}_{3}^{-}(a q)\) c. \(\mathrm{Cr}(\mathrm{NCS})_{6}^{4-}(a q)+\mathrm{Ce}^{4+}(a q) \stackrel{\text { Acid }}{\longrightarrow}\) \(\mathrm{Cr}^{3+}(a q)+\mathrm{Ce}^{3+}(a q)+\mathrm{NO}_{3}^{-}(a q)+\mathrm{CO}_{2}(g)+\mathrm{SO}_{4}{ }^{2-}(a q)\) d. \(\operatorname{CrI}_{3}(s)+\mathrm{Cl}_{2}(g) \stackrel{\text { Base }}{\longrightarrow}\) \(\operatorname{CrO}_{4}{ }^{2-}(a q)+\mathrm{IO}_{4}^{-}(a q)+\mathrm{Cl}^{-}(a q)\) e. \(\mathrm{Fe}(\mathrm{CN})_{6}^{4-}(a q)+\mathrm{Ce}^{4+}(a q) \stackrel{\text { Base }}{\longrightarrow}\) \(\mathrm{Ce}(\mathrm{OH})_{3}(s)+\mathrm{Fe}(\mathrm{OH})_{3}(s)+\mathrm{CO}_{3}^{2-}(a q)+\mathrm{NO}_{3}^{-}(a q)\)

The compound with the formula \(\mathrm{TII}_{3}\) is a black solid. Given the following standard reduction potentials, $$ \begin{aligned} \mathrm{Tl}^{3+}+2 \mathrm{e}^{-} \longrightarrow \mathrm{Tl}^{+} & \mathscr{E}^{\circ}=1.25 \mathrm{~V} \\ \mathrm{I}_{3}^{-}+2 \mathrm{e}^{-} \longrightarrow 3 \mathrm{I}^{-} & \mathscr{E}^{\circ}=0.55 \mathrm{~V} \end{aligned} $$ would you formulate this compound as thallium(III) iodide or thallium(I) triiodide?

What is the maximum work that can be obtained from a hydrogen-oxygen fuel cell at standard conditions that produces \(1.00 \mathrm{~kg}\) water at \(25^{\circ} \mathrm{C} ?\) Why do we say that this is the maximum work that can be obtained? What are the advantages and disadvantages in using fuel cells rather than the corresponding combustion reactions to produce electricity?

The electrolysis of \(\mathrm{BiO}^{+}\) produces pure bismuth. How long would it take to produce \(10.0 \mathrm{~g}\) Bi by the electrolysis of a \(\mathrm{BiO}^{+}\) solution using a current of \(25.0 \mathrm{~A} ?\)

Sketch the galvanic cells based on the following overall reactions. Show the direction of electron flow, the direction of ion migration through the salt bridge, and identify the cathode and anode. Give the overall balanced equation. Assume that all concentrations are \(1.0 M\) and that all partial pressures are \(1.0 \mathrm{~atm}\).

See all solutions

Recommended explanations on Chemistry Textbooks

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