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Question
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
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