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### Course: High school chemistry>Unit 6

Lesson 1: Thermal energy and equilibrium

# Thermal energy, temperature, and heat

Thermal energy refers to the kinetic energy of randomly moving particles in a substance. Particles can have translational, rotational, and/or vibrational kinetic energy, depending on the state of matter. Temperature is a measure of the average kinetic energy of the particles in a substance. Heat is thermal energy that transfers into or out of a system. Heat can transfer by conduction, convection, or radiation. Created by Mahesh Shenoy.

## Want to join the conversation?

• What would the thermal energy be measured in when Mahesh computes it at ?
• The thermal energy is the total sum of the kinetic energy in the particles and there is 300 particles with each containing on average, 2 kinetic energy. So I think you do 300*2 = 600 kinetic energy which is the thermal energy.
(1 vote)
• Hi there, I had a question about when they were explaining at the start what is thermal energy, isn't thermal energy also the process where heat is transferred from a hotter substance to a cooler substance resulting in the two substances reaching equilibrium?
(1 vote)
• Thermal energy refers to the kinetic energy of the particles in a substance. Objects in thermal contact of differing temperatures will transfer energy (heat to the cooler substance) and reach thermal equilibrium. This process is called heat transfer. Conduction, convection and radiation are methods of heat transfer.
I hope this explanation helps! =D