---
title: "A student investigates the elementary gas-phase reaction represented by the equation below.  \\[ \\text{AB(g)} + \\text{C(g)} \\rightleftharpoons \\text{A(g)} + \\text{BC(g)} \\quad \\Delta H^\\circ = +60\\text{ kJ/mol}_{\\text{rxn}} \\]  The activation energy for the forward reaction, \\(E_{a,\\text{fwd}}\\), is determined to be \\(140\\text{ kJ/mol}_{\\text{rxn}}\\). What is the activation energy for the reverse reaction, \\(E_{a,\\text{rev}}\\)?"
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url: "https://nerd-notes.com/ubq/119724/"
date_modified: "2026-08-21T08:12:09+00:00"
---

# A student investigates the elementary gas-phase reaction represented by the equation below.

\[ \text{AB(g)} + \text{C(g)} \rightleftharpoons \text{A(g)} + \text{BC(g)} \quad \Delta H^\circ = +60\text{ kJ/mol}_{\text{rxn}} \]

The activation energy for the forward reaction, \(E_{a,\text{fwd}}\), is determined to be \(140\text{ kJ/mol}_{\text{rxn}}\). What is the activation energy for the reverse reaction, \(E_{a,\text{rev}}\)?

A student investigates the elementary gas-phase reaction represented by the equation below.

\[ \text{AB(g)} + \text{C(g)} \rightleftharpoons \text{A(g)} + \text{BC(g)} \quad \Delta H^\circ = +60\text{ kJ/mol}_{\text{rxn}} \]

The activation energy for the forward reaction, \(E_{a,\text{fwd}}\), is determined to be \(140\text{ kJ/mol}_{\text{rxn}}\). What is the activation energy for the reverse reaction, \(E_{a,\text{rev}}\)?

- **A.** \(60\text{ kJ/mol}_{\text{rxn}}\)
- **B.** \(80\text{ kJ/mol}_{\text{rxn}}\)
- **C.** \(140\text{ kJ/mol}_{\text{rxn}}\)
- **D.** \(200\text{ kJ/mol}_{\text{rxn}}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119724/*