The internal energy of a system is the total of the random kinetic and potential energies of all its molecules. For an ideal gas there are no intermolecular forces, so it is entirely kinetic and depends only on the temperature. Warm the gas and watch both the molecular speeds and the internal energy rise.
MissionPredict what the internal energy of a fixed mass of ideal gas depends on.Streak 0Best 0
For a fixed mass of ideal gas, the internal energy depends only on the:
temperature T300 K
mean molecular KE = ₃⁄₂ kT6.2 × 10⁻²¹ J
internal energy (total random energy)rises with T
Internal energy is the sum of the random kinetic and potential energies of every molecule. For an ideal gas it is all kinetic, so it is fixed by the temperature alone.