# Cp and Cv Relationship for an Ideal Gas

When precise values are not needed or available, the following values can be used near room temperature:

Monatomic Gases (ex. Ar)

Diatomic Gases (ex. O2)

The definition of enthalpy is:

For ideal gases , this simplifies to:

The differential form of this equation is:

But, we showed on the previous two pages that:

Therefore:

Dividing each term by dT yields:

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