An exothermic reaction proceeding in an adiabatic reactor results in a product temperature that is ______________ the feed temperature?
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Answer: B. Is always greater than
Explanation
In an adiabatic reactor, the heat released by an exothermic reaction increases the temperature. Enthalpy changes convert chemical energy into sensible heat of the reacting mixture. As a result, the product temperature is always greater than the feed temperature. Adiabatic reactors operate without any heat exchange with the external surroundings. Exothermic reactions generate thermal energy internally during the chemical conversion process. Energy balances relate reaction enthalpy directly to the resulting temperature increase.
Exothermic reactor design must prevent dangerous runaway temperatures from damaging equipment. Intercooling between reactor stages is commonly employed to manage high temperature rises. Industrial ammonia synthesis reactors utilize staged cooling to control adiabatic temperature gains. Option A is false because exothermic reactions release heat and raise the temperature. Option C is false because only endothermic reactions result in lower product temperatures. Option D is incorrect because exothermic reactions always produce a higher temperature.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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