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Calculate which of two reaction is more exothermic

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Which reaction is more exothermic?
A reaction with Keq=500 or a reaction with Keq=0.002?

© BrainMass Inc. brainmass.com October 24, 2018, 5:06 pm ad1c9bdddf

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(Please refer to the attached file, as the formatting of Greek letters, etc. in this HTML version may be jumbled.)

To answer this question, you will need the following equations, as well as an understanding of some basic thermodynamic concepts. You should be familiar with these equations from your lectures. If not, they will be available in your textbook. EXAM TIPS: When exam time comes, ...

Solution Summary

In addition to a full answer, this problem solution provides an explanation of how to approach deciding which reaction is more exothermic, when you have a limited amount of information. The problem only provided the Keq values, without stating other experimental conditions (such as temperature or reaction components). This creates a challenging and tricky situation for the student -- you will need to understand thermodynamic equations and relationships, and use that understanding to reason (rather than calculate) which of the two reactions is more exothermic. Exam tips for this type of problem are also shown in the html version of the solution (but not in the attachment).

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