Vocabulary
Key concepts
ES
100

a measure of the average kinetic energy of the molecules of a thing.

What is temperature?

100

For things at the same temperature, the thing with more molecules has more total kinetic energy (thermal energy) than the thing with fewer molecules.

What is key concept 8?

100

 Warmer objects transfer energy to cooler objects when they are in contact. 

What is ES2?

200

A number that summarizes a set of data and that can be computed by adding all the numbers in a list and then dividing by the number of numbers in the list

What is average?

200

When two things are in contact, their molecules collide, and kinetic energy transfers from the faster‑moving molecules to the slower‑moving molecules.

What is key concept 5?

200

The size of the objects in contact affects the amount of energy transfer between them and the amount of temperature change.

What is ES3?

300

A balanced state in which a system is stable, such as when two or more samples are at the same temperature.

What is equilibrium?

300

The molecules of a system will transfer energy until the system reaches a stable state known as equilibrium, in which all of the molecules are moving at about the same speed.

What is key concept 7?

300

The temperature of an object is related to the kinetic energy of its molecules, which increases as the speed of the molecules increases. 

What is ES1?

400

When something stays mostly the same over time.

What is stability? 
400

At equilibrium, the average kinetic energy (temperature) of the molecules in the system is the total kinetic energy (thermal energy) evenly divided by the number of molecules in the system.

What is Key Concept 9?

500

The total kinetic energy of all the molecules that make up a sample.

What is thermal energy? 

500

Energy isn’t created or destroyed. Therefore, as energy transfers, it increases in one part of the system as it decreases in another part of the system. The total energy of a system doesn’t change.

What is key concept 6?