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Thermal Chemistry

I'm having problems understanding the ideas in the topic of thermal chemistry and would appreciate any sort of overview of the main concepts you could provide.

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Please see attached.

The basic idea behind thermochemistry is that when a chemical reaction takes place, some amount of energy is given off or absorbed. There are many different definitions of the "energy" given off in the chemical reaction - this mainly depends on the conditions. The following table illustrates this:

delta G gibbs free energy reaction takes place under
constant pressure, volume
is allowed to change

delta A helmholtz free energy reaction takes place under
constant volume, pressure is
allowed to change

delta H enthalpy usually for reactions in a
calorimeter (constant volume
& pressure)

There can be a lot of confusion about when to use which of these - basically the best thing to do is to do lots of practice problems ...

Solution Summary

The solution provides a brief overview of the topic of thermal chemistry, including explanations of Gibbs' free energy, enthalpy, endo/exothermic reactions and more.