Q38.The (S∘) of the following substances are: CH4 g)186.2JK−1 mol−1 O2 (g) 205.2JK−1 mol−1 CO2( g)213.6JK−1 mol−1 H2O(g) 69.9.JK −1 mol−1 The entropy change (ΔS∘) for the reaction CH4( g) + 2O2( g) →CO2( g) + 2H2O (l) is: (1) −312.5 J K−1 mol−1 (2) −242.8JK−1 mol−1 (3) −108.1JK−1 mol−1 (4) −37.6 J K−1 mol−1
What This Question Tests
This question tests the calculation of standard entropy change for a reaction using standard molar entropies of reactants and products, with a slight potential ambiguity regarding the physical state of water that needs careful interpretation.
Concepts Tested
Formulas Used
ΔS° = ΣS°(products) - ΣS°(reactants)
📚 NCERT Sections This Tests
2.6 — In The Button Cells Widely Used In Watches And Other Devices The Following
Chemistry Class 11 · Chapter 2
2.6 In the button cells widely used in watches and other devices the following reaction takes place: Zn(s) + Ag2O(s) + H2O(l) ® Zn2+(aq) + 2Ag(s) + 2OH–(aq) Determine DrGo and Eo for the reaction.
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Chemistry Class 11 · Chapter 1
1.35 Henry’s law constant for the molality of methane in benzene at 298 K is 4.27 × 105 mm Hg. Calculate the solubility of methane in benzene at 298 K under 760 mm Hg.
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Chemistry Class 11 · Chapter 3
3.21 The following data were obtained during the first order thermal decomposition of SO2Cl2 at a constant volume. SO2 Cl 2 g SO 2 g Cl 2 g Experiment Time/s–1 Total pressure/atm 1 0 0.5 2 100 0.6 Calculate the rate of the reaction when total pressure is 0.65 atm.
📋 Question Details
- Chapter
- Thermodynamics & Thermochemistry
- Topic
- Entropy change of reaction
- Year
- 2014
- Shift
- 12 Apr Online
- Q Number
- Q38
- Type
- MCQ
- NCERT Ref
- Class 11 Chemistry Ch 6: Thermodynamics
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