Thermal energy is the total ……….. of the particles that make up a substance.

Explanation

**Step-by-Step Solution:**

1. **Understanding Thermal Energy**: Thermal energy refers to the energy that comes from the temperature of a substance. It is associated with the motion of particles within that substance.

2. **Identifying the Nature of Particles**: The particles that make up a substance can be atoms or molecules. These particles are always in motion, and their movement contributes to the thermal energy of the substance.

3. **Defining Kinetic Energy**: Kinetic energy is the energy that an object possesses due to its motion. The faster the particles move, the more kinetic energy they have.

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