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Benzoic acid is a common standard used i...

Benzoic acid is a common standard used in Bomb calorimaters, which maintain a constant volume. If 1.2 gm of benzoic acid gives off 31.723 J of energy when burned in the presence of excess oxygen at an initial temperature of `24.6^(@)C`, calculate heat capacity at constant volume of final product mixture if final temperature is `47.34^(@)C`. Also calculate, W and `Delta U` for the given amount, assuming ideal gas behaviour.

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The correct Answer is:
`C=1.395" J/K", W=0, deltaU=-31.723 J`
`q_(v)=nC_(v)dt`
`Cv=1.395 Jk^(-1)`
`w=0`
`DeltaU=q_(v)=31.723 J`
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