A voltaic cell that uses the reaction Tl3+(aq) + 2 Cr2+(aq) → Tl+(aq) + 2 Cr3+(aq) has a measured standard cell potential of +1.19 V. (c) Sketch the voltaic cell, label the anode and cathode, and indicate the direction of electron flow.

Verified step by step guidance

Identify the half-reactions involved in the voltaic cell. The oxidation half-reaction is Cr2+ → Cr3+ + e−, and the reduction half-reaction is Tl3+ + 2e− → Tl+.

Determine which electrode serves as the anode and which serves as the cathode. The anode is where oxidation occurs, so Cr2+ is oxidized to Cr3+. The cathode is where reduction occurs, so Tl3+ is reduced to Tl+.

Label the anode and cathode in your sketch. The anode is the electrode where Cr2+ is oxidized, and the cathode is the electrode where Tl3+ is reduced.

Indicate the direction of electron flow in the external circuit. Electrons flow from the anode to the cathode in a voltaic cell.

Draw the salt bridge connecting the two half-cells, which allows ions to flow and maintain electrical neutrality.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Voltaic Cell Structure

A voltaic cell, also known as a galvanic cell, consists of two half-cells connected by a salt bridge. Each half-cell contains an electrode immersed in an electrolyte solution. The anode is where oxidation occurs, releasing electrons, while the cathode is where reduction takes place, accepting electrons. Understanding this structure is essential for sketching the cell and identifying the flow of electrons.

Oxidation and Reduction Reactions

In redox reactions, oxidation refers to the loss of electrons, while reduction refers to the gain of electrons. In the given reaction, Tl3+ is reduced to Tl+, and Cr2+ is oxidized to Cr3+. Recognizing which species undergoes oxidation and reduction is crucial for labeling the anode and cathode in the voltaic cell sketch.

Standard Cell Potential

The standard cell potential (E°) is a measure of the voltage produced by a voltaic cell under standard conditions. It indicates the driving force behind the redox reaction, with a positive value suggesting a spontaneous reaction. In this case, the +1.19 V indicates that the reaction is favorable, which is important for understanding the overall function of the voltaic cell.

Recommended video:

Guided course

01:27

Standard Cell Potential

Related Practice

Textbook Question

(b) Write the half-reaction that occurs at a hydrogen electrode in acidic aqueous solution when it serves as the anode of a voltaic cell.

Textbook Question

A voltaic cell that uses the reaction PdCl₄^2-(aq) + Cd(s) → Pd(s) + 4 Cl^-(aq) + Cd²⁺(aq) has a measured standard cell potential of +1.03 V. (a) Write the two half-cell reactions.

views

Textbook Question

A voltaic cell that uses the reaction PdCl₄^2-(aq) + Cd(s) → Pd(s) + 4 Cl^-(aq) + Cd²⁺(aq) has a measured standard cell potential of +1.03 V. (b) By using data from Appendix E, determine E°_red for the reaction involving Pd.

Textbook Question

A voltaic cell that uses the reaction PdCl₄^2-(aq) + Cd(s) → Pd(s) + 4 Cl^-(aq) + Cd²⁺(aq) has a measured standard cell potential of +1.03 V. (c) Sketch the voltaic cell, label the anode and cathode, and indicate the direction of electron flow