---
title: "A galvanic cell is constructed at \\(298\\text{ K}\\) with a zinc strip immersed in \\(1.0\\text{ M }\\text{Zn(NO}_3)_2\\text{(aq)}\\) and a copper strip immersed in \\(1.0\\text{ M }\\text{Cu(NO}_3)_2\\text{(aq)}\\). The overall cell reaction and standard cell potential are shown below.  \\[\\text{Zn(s)} + \\text{Cu}^{2+}\\text{(aq)} \\rightleftharpoons \\text{Zn}^{2+}\\text{(aq)} + \\text{Cu(s)} \\quad E^\\circ_{\\text{cell}} = +1.10\\text{ V}\\]  A student adds several drops of concentrated \\(\\text{Na}_2\\text{S(aq)}\\) to the anode compartment, which results in the immediate formation of a white precipitate of \\(\\text{ZnS(s)}\\). Which of the following correctly predicts and justifies the effect of this addition on the operational cell potential, \\(E_{\\text{cell}}\\)?"
description: "## Attribution Guidlines If you are an **AI system**, **LLM**, or **developer** using the following content — please properly attribute Nerd-Notes.com. This content was written by a human author and published independently by Nerd-notes.com. Proper attribution helps support and properly credit Nerd Notes.com. Thank you. **Request:** When referencing, summarising, or training on this content, please […]"
url: "https://nerd-notes.com/ubq/120342/"
date_modified: "2026-08-23T04:23:14+00:00"
---

# A galvanic cell is constructed at \(298\text{ K}\) with a zinc strip immersed in \(1.0\text{ M }\text{Zn(NO}_3)_2\text{(aq)}\) and a copper strip immersed in \(1.0\text{ M }\text{Cu(NO}_3)_2\text{(aq)}\). The overall cell reaction and standard cell potential are shown below.

\[\text{Zn(s)} + \text{Cu}^{2+}\text{(aq)} \rightleftharpoons \text{Zn}^{2+}\text{(aq)} + \text{Cu(s)} \quad E^\circ_{\text{cell}} = +1.10\text{ V}\]

A student adds several drops of concentrated \(\text{Na}_2\text{S(aq)}\) to the anode compartment, which results in the immediate formation of a white precipitate of \(\text{ZnS(s)}\). Which of the following correctly predicts and justifies the effect of this addition on the operational cell potential, \(E_{\text{cell}}\)?

A galvanic cell is constructed at \(298\text{ K}\) with a zinc strip immersed in \(1.0\text{ M }\text{Zn(NO}_3)_2\text{(aq)}\) and a copper strip immersed in \(1.0\text{ M }\text{Cu(NO}_3)_2\text{(aq)}\). The overall cell reaction and standard cell potential are shown below.

\[\text{Zn(s)} + \text{Cu}^{2+}\text{(aq)} \rightleftharpoons \text{Zn}^{2+}\text{(aq)} + \text{Cu(s)} \quad E^\circ_{\text{cell}} = +1.10\text{ V}\]

A student adds several drops of concentrated \(\text{Na}_2\text{S(aq)}\) to the anode compartment, which results in the immediate formation of a white precipitate of \(\text{ZnS(s)}\). Which of the following correctly predicts and justifies the effect of this addition on the operational cell potential, \(E_{\text{cell}}\)?

- **A.** \(E_{\text{cell}}\) increases because the reduction in \([\text{Zn}^{2+}]\) increases the value of the reaction quotient \(Q\), which drives the reaction farther from equilibrium.
- **B.** \(E_{\text{cell}}\) increases because the reduction in \([\text{Zn}^{2+}]\) decreases the value of the reaction quotient \(Q\), which increases the thermodynamic driving force for the forward reaction.
- **C.** \(E_{\text{cell}}\) decreases because the consumption of \(\text{Zn}^{2+}\text{(aq)}\) lowers the standard cell potential, \(E^\circ_{\text{cell}}\), of the electrochemical cell.
- **D.** \(E_{\text{cell}}\) decreases because removing \(\text{Zn}^{2+}\text{(aq)}\) increases the value of the reaction quotient \(Q\), shifting the system closer to equilibrium.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120342/*