**Understanding Reaction Spontaneity Based on Temperature: An Explanation with Examples****Objective:** To demonstrate why certain chemical reactions are spontaneous at low temperatures while others are non-spontaneous regardless of temperature.**Reactions:**(a) \( \text{CH}_4 (\text{g}) + 2\text{O}_2 (\text{g}) \rightarrow 2\text{H}_2\text{O} (\text{l}) + \text{CO}_2 (\text{g}) \) (b) \( 2\text{C}_2\text{H}_6 (\text{g}) + 7\text{O}_2 (\text{g}) \rightarrow 6\text{H}_2\text{O} (\text{l}) + 4\text{CO}_2 (\text{g}) \) (exothermic)**Problem:**Show why reaction (b) is spontaneous only at low temperatures, while reaction (a) is always non-spontaneous.### Explanation:**1. Reaction Equations:** - **Reaction (a):** \[ \text{CH}_4 (\text{g}) + 2\text{O}_2 (\text{g}) \rightarrow 2\text{H}_2\text{O} (\text{l}) + \text{CO}_2 (\text{g}) \] - **Reaction (b):** \[ 2\text{C}_2\text{H}_6 (\text{g}) + 7\text{O}_2 (\text{g}) \rightarrow 6\text{H}_2\text{O} (\text{l}) + 4\text{CO}_2 (\text{g}) \, (\text{{exothermic}}) \]**2. Enthalpy (ΔH) and Entropy (ΔS) considerations:** - **Exothermic Reactions:** These reactions release heat, denoted by a negative ΔH. - **Endothermic Reactions:** These reactions absorb heat, denoted by a positive ΔH. For spontaneity: - Spontaneous at all temperatures: ΔG = ΔH - TΔS < 0 when ΔH is negative and ΔS positive. - Spontaneous at low temperatures: When

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8 Show why reaction is spontaneous only hure, while reaction (a) is always at low tempre non spontaneous a) CH4 (g) + 20₂(g) → 2 H₂O (l) + CO₂ (g) (endothermic) b) 2C₂H6 (g) +702(g) → 6 H₂0 (e) + 4 (0₂ (g) (@xothermic)

8 Show why reaction is spontaneous only hure, while reaction (a) is always at low tempre non spontaneous a) CH4 (g) + 20₂(g) → 2 H₂O (l) + CO₂ (g) (endothermic) b) 2C₂H6 (g) +702(g) → 6 H₂0 (e) + 4 (0₂ (g) (@xothermic)

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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13)The reaction 2NOBr(g) → 2NO(g) + Br₂(g) has AG° = 6.28 kJ. a. Calculate Q when [NOBr] = 0.15 M, [NO] = 0.096 M, and [Br₂] = 0.081 M. b. Calculate AG for the reaction at 150°C. c. Is this reaction spontaneous or non-spontaneous under these conditions? Scanned with CamScanner
Consider the formation reaction of water, the hydrogen balloon reaction: 2 H,(g) + 0,(g) → 2 H,0(g) Which ONE of the following statements is FALSE for this reaction? ΑΔΗ<0 В AS < 0 The reaction is spontaneous at all C temperatures. AG = 0 at some very high D temperatures.
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