Heating and cooling can cause changes in the properties of materials, but not all materials respond the same way to being heated and cooled.
Learning Goal 1b
Many kinds of changes occur faster under hotter conditions.
Learning Goal 4a
When a new material is made by combining two or more materials, it has properties that are different from the original materials.
Learning Goal 4b
A lot of different materials can be made from a small number of basic kinds of materials.
Learning Goal 6
All materials have certain physical properties, such as strength, hardness, flexibility, durability, resistance to water and fire, and ease of conducting heat.
For Grades: 6-8
Learning Goal 3ab
Atoms and molecules are perpetually in motion. Increased temperature means greater average energy of motion, so most substances expand when heated.
Learning Goal 3
In solids, the atoms or molecules are closely locked in position and can only vibrate. In liquids, they have higher energy, are more loosely connected, and can slide past one another; some molecules may get enough energy to escape into a gas. In gases, the atoms or molecules have still more energy and are free of one another except during occasional collisions.
Learning Goal 4
The temperature and acidity of a solution influence reaction rates. Many substances dissolve in water, which may greatly facilitate reactions between them.