Skip to main content
Ch.19 - Electrochemistry
Tro - Chemistry: A Molecular Approach 4th Edition
Tro4th EditionChemistry: A Molecular ApproachISBN: 9780134112831Non è quello che usi tu?Cambia libro di testo
Tutti i libri di testoTro 4th EditionCh.19 - ElectrochemistryProblema 95
Capitolo 19, Problema 95

Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution. a. NaBr(aq) b. PbI2(aq) c. Na2SO4(aq)

Guida verificata passo dopo passo
1
Identify the ions present in each aqueous solution. For NaBr(aq), the ions are Na^+ and Br^-. For PbI_2(aq), the ions are Pb^2+ and I^-. For Na_2SO_4(aq), the ions are Na^+, SO_4^2-, and H_2O.
Determine the possible half-reactions at the anode and cathode. At the anode, oxidation occurs, and at the cathode, reduction occurs. Consider the standard reduction potentials to identify which species will be oxidized and reduced.
For NaBr(aq), at the anode, Br^- ions are oxidized to Br_2 gas. The half-reaction is: 2Br^- \(\rightarrow\) Br_2 + 2e^-. At the cathode, water is reduced to hydrogen gas: 2H_2O + 2e^- \(\rightarrow\) H_2 + 2OH^-.
For PbI_2(aq), at the anode, I^- ions are oxidized to I_2. The half-reaction is: 2I^- \(\rightarrow\) I_2 + 2e^-. At the cathode, Pb^2+ ions are reduced to Pb metal: Pb^2+ + 2e^- \(\rightarrow\) Pb.
For Na_2SO_4(aq), at the anode, water is oxidized to oxygen gas: 2H_2O \(\rightarrow\) O_2 + 4H^+ + 4e^-. At the cathode, water is reduced to hydrogen gas: 2H_2O + 2e^- \(\rightarrow\) H_2 + 2OH^-.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
3m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Electrolysis

Electrolysis is a chemical process that uses electrical energy to drive a non-spontaneous reaction. In this process, an electric current is passed through an electrolyte, causing the decomposition of the compound into its constituent elements or ions. The reactions occur at two electrodes: oxidation at the anode and reduction at the cathode.
Video consigliato:
Percorso guidato
01:21
The Electrolytic Cell

Half-Reactions

Half-reactions are the individual oxidation or reduction reactions that occur at the electrodes during electrolysis. Each half-reaction shows the transfer of electrons and the change in oxidation states of the species involved. By writing half-reactions, one can clearly identify what is being oxidized and what is being reduced in the overall electrochemical process.
Video consigliato:
Percorso guidato
07:19
Redox Half Reactions Example

Electrolyte Composition

The composition of the electrolyte determines the ions available for the electrolysis process. Different electrolytes, such as NaBr, PbI2, and Na2SO4, will produce different ions in solution, which can lead to various products at the electrodes. Understanding the dissociation of these compounds in water is crucial for predicting the half-reactions that will occur during electrolysis.
Video consigliato:
Percorso guidato
02:50
Electrolytes and Strong Acids
Pratica correlata
Domanda del libro di testo

What products are obtained in the electrolysis of a molten mixture of KI and KBr?

1080
views
1
rank
Domanda del libro di testo

Make a sketch of an electrolysis cell that electroplates copper onto other metal surfaces. Label the anode and the cathode and indicate the reactions that occur at each.

887
views
Domanda del libro di testo

Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution. b. KCl(aq) c. CuBr2(aq)

Domanda del libro di testo

What products are obtained in the electrolysis of molten NaI?

1416
views
1
comments
Domanda del libro di testo

Write equations for the half-reactions that occur at the anode and cathode for the electrolysis of each aqueous solution. a. Ni(NO3)2(aq)

3029
views