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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.

Solution Preview

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.

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