The internal energy of a fixed mass of an ideal gas depends on

B. Temperature

The internal energy of a fixed mass of an ideal gas depends on:

B. Temperature

This is because in an ideal gas:

• The molecules are assumed to be point-like with negligible volume.
• There are no intermolecular forces between the gas molecules.
• The only contributor to the internal energy is the kinetic energy of the gas molecules.

Since the temperature is directly proportional to the average kinetic energy of the gas molecules, the internal energy of an ideal gas depends solely on temperature.

The other options are not relevant for an ideal gas:

• A. Pressure: While pressure and temperature are related in ideal gases (through the ideal gas law), pressure itself doesn’t directly determine the internal energy.
• C. Volume: In an ideal gas, the molecules are assumed to have negligible volume, so the container’s volume doesn’t affect the internal energy as long as the gas molecules have enough space to move freely.