The entropy (So) of the following substances are: CH4 (g) 186.2 J K-1 mol-1 O2 (g) 205.0 J K-1 mol-1 CO2 (g) 213.6 J K-1 mol-1 H2O (g) 69.9 J K-1 mol-1 The entropy change (Δ So) for the reaction CH4(g) + 2O2(g) arrow CO2(g) + 2H2O(l) is :

Question

The entropy (So) of the following substances are: CH4 (g) 186.2 J K-1 mol-1 O2 (g) 205.0 J K-1 mol-1 CO2 (g) 213.6 J K-1 mol-1 H2O (g) 69.9 J K-1 mol-1 The entropy change (Δ So) for the reaction CH4(g) + 2O2(g) arrow CO2(g) + 2H2O(l) is : (A) -312.5 J K-1 mol-1 (B) -242.8 J K-1 mol-1 (C) -108.1 J K-1 mol-1 (D) -37.6 J K-1 mol-1

Tardigrade Admin · Accepted Answer

underset186.2CH4(g) + underset2052O2(g) arrow underset213.6CO2(g) + underset69.92H2O(ℓ) Δ S° = ∑(s°P - ∑(s°)R =[213.6 + (2× 69.9)] - [186.2 + 2 × 205] = 353.4 - 596.2 = -242.8 J/mol K

$- 312.5 J K^{- 1} m o l^{- 1}$

$- 242.8 J K^{- 1} m o l^{- 1}$

$- 108.1 J K^{- 1} m o l^{- 1}$

$- 37.6 J K^{- 1} m o l^{- 1}$

$186.2 C H_{4 (g)} + 205 2 O_{2 (g)} \to 213.6 C O_{2 (g)} + 69.9 2 H_{2} O (ℓ)$

$Δ S^{\circ} = \sum (s_{P}^{\circ} - \sum (s^{\circ})_{R}$

$= [213.6 + (2 \times 69.9)] - [186.2 + 2 \times 205]$

$= 353.4 - 596.2$

$= - 242.8 J / m o l K$

Q. The entropy (So) of the following substances are : CH4​(g)186.2JK−1mol−1 O2​(g)205.0JK−1mol−1 CO2​(g)213.6JK−1mol−1 H2​O(g)69.9JK−1mol−1 The entropy change (ΔSo) for the reaction CH4​(g)+2O2​(g)→CO2​(g)+2H2​O(l) is :

−312.5JK−1mol−1

−242.8JK−1mol−1

−108.1JK−1mol−1

−37.6JK−1mol−1

186.2CH4(g)​​+2052O2(g)​​→213.6CO2(g)​​+69.92H2​O(ℓ)​ ΔS∘=∑(sP∘​−∑(s∘)R​ =[213.6+(2×69.9)]−[186.2+2×205] =353.4−596.2 =−242.8J/molK

$- 312.5 J K^{- 1} m o l^{- 1}$

$- 242.8 J K^{- 1} m o l^{- 1}$

$- 108.1 J K^{- 1} m o l^{- 1}$

$- 37.6 J K^{- 1} m o l^{- 1}$

$186.2 C H_{4 (g)} + 205 2 O_{2 (g)} \to 213.6 C O_{2 (g)} + 69.9 2 H_{2} O (ℓ)$

$Δ S^{\circ} = \sum (s_{P}^{\circ} - \sum (s^{\circ})_{R}$

$= [213.6 + (2 \times 69.9)] - [186.2 + 2 \times 205]$

$= 353.4 - 596.2$

$= - 242.8 J / m o l K$