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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

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 _______.

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प्रश्न

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 _______. 

पर्याय

  • –801.7 J K–1

  • 801.7 J K–1

  • 0.8017 J K–1

  • –0.8017 J K–1

MCQ
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उत्तर

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 

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पाठ 4: Chemical Thermodynamics - Exercises [पृष्ठ ८७]

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बालभारती Chemistry [English] Standard 12 Maharashtra State Board
पाठ 4 Chemical Thermodynamics
Exercises | Q 1.07 | पृष्ठ ८७

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