Temperature and Kinetic Energy

• Explore the connection between the temperature of a substance and its kinetic energy.

• Explain how temperature affects the speed and kinetic energy of tiny molecules.

• Learn the key differences between the scientific concepts of heat and temperature.

• Understand what absolute zero is and what it means for particle motion.

Key Vocabulary

Kinetic Energy

Kinetic energy is the energy of motion. All things are made of moving molecules with this energy.

Temperature

This is a measure of the average kinetic energy of the molecules that make up a substance.

Absolute Zero

This is the lowest possible temperature where the motion of all particles theoretically stops completely.

Heat

Heat is the form of energy that is transferred from a warmer object to a cooler one.

What are Temperature and Kinetic Energy?

• Kinetic energy is the energy of moving molecules.

• Temperature measures the average kinetic energy of these molecules.

• Faster molecules mean higher kinetic energy and a higher temperature.

Kinetic Energy Distribution

• Particles in a substance have a wide range of kinetic energies.

• ​Most particles have an energy level near the middle of this range.

• Some move slowly with low energy, and some move fast with high energy.

• Increasing the temperature makes more particles move at much higher speeds.

Absolute Zero

• Absolute zero (0 K) is the coldest temperature possible.

• At this temperature, particles stop moving.

• It is the starting point for the Kelvin scale.

Kelvin Scale

• The Kelvin scale measures temperature starting from absolute zero.

• It does not use negative numbers.

• A temperature of 300 K has three times the average kinetic energy as 100 K because Kelvin is proportional to particle energy.

Heat is Energy in Transit

• Temperature is a measure of the average kinetic energy of an object's molecules.

• Heat is energy that transfers from a warmer object to a cooler one.

• This energy transfer happens when molecules from the two objects collide.

• Temperature measures the average kinetic energy of the particles in a substance.

• Heat is the transfer of energy from a warmer object to a cooler one.

• At the same temperature, particles have the same average kinetic energy but individual speeds.

• The Kelvin scale relates to kinetic energy, where particle motion stops at absolute zero.