Select the most appropriate option. If the standard enthalpy of formation of methanol is –238.9 kJ mol–1 then entropy change of the surroundings will be _______. - Chemistry

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MCQ

Select the most appropriate option.

If the standard enthalpy of formation of methanol is –238.9 kJ mol–1 then entropy change of the surroundings will be _______. 

Options

  • –801.7 J K–1

  • 801.7 J K–1

  • 0.8017 J K–1

  • –0.8017 J K–1

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Solution

If the standard enthalpy of formation of methanol is –238.9 kJ mol–1 then entropy change of the surroundings will be 801.7 J K–1.

Explanation:

For standard state, temperature = 298 K

`triangle "S"_"surr" = - (triangle "H")/"T" = - ((- 238.9  "kJ"))/(298 "k")`

= + 0.8017 kJ K-1

= 801.7 J K-1 

Concept: Enthalpy (H)
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Chapter 4: Chemical Thermodynamics - Exercises [Page 87]

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Balbharati Chemistry 12th Standard HSC for Maharashtra State Board
Chapter 4 Chemical Thermodynamics
Exercises | Q 1.07 | Page 87

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