Formula Ideal Gas Internal energy    Degrees of freedom    Temperature    Stoffmenge

Internal energy

Unit
Internal energy is the total energy of molecules or atoms of an ideal gas that is in thermodynamic equilibrium.

Degrees of freedom

Unit
Number of degrees of freedom of a particle of the gas. In the three-dimensional case and without particles being able to rotate and vibrate, $$f = 3$$. The more degrees of freedom the gas has, the greater the internal energy of the system.

Temperature

Unit
Absolute temperature of the system, that is the temperature of a gas. The greater the temperature, the greater the internal energy.

Stoffmenge

Unit
The amount of substance $$n$$ is the ratio between the number of particles $$N$$ and the Avogardo constant $$N_{\text A} = 6 \cdot 10^{23}$$:$$n = \frac{N}{N_{\text A}}$$

So in one mole of gas there are $$6 \cdot 10^{23}$$ gas particles.

Gas constant

Unit
Gas constant is a physical constant appearing in thermodynamics. It has the following value: $$R ~=~ 8.314 \, \frac{ \mathrm{J} }{ \mathrm{K} \, \mathrm{mol} }$$