The statement is true; substances contain varying amounts of thermal energy due to different particle types and their energy. Temperature influences these energy levels and can change a substance's state.
Substances contain different amounts of thermal energy because of the variations in the kinetic energy of their atoms or molecules. The answer to the student's question is true: different types of particles, their motions, and the strength of intermolecular forces contribute to how much thermal energy a substance contains.
At a given temperature, substances may exhibit more intense translations, vibrations, or rotations of atoms or molecules, indicating a higher kinetic energy - this results in greater internal energy and thus more thermal energy. Cooling a substance decreases these motions and lowers kinetic energy. Additionally, phase changes, where substances transition from solid to liquid to gas with temperature changes, are a direct consequence of variations in thermal energy due to modifications in kinetic energy of particles and intermolecular forces.
In conclusion, the total internal energy of a substance, which includes thermal energy, depends on the kinetic and potential energy of its particles. Temperature changes can alter the kinetic energy and thereby the state of a substance.