This learning progression relates to the Next Generation Science Standards’ Arguing from Evidence science and engineering practice.
Particulate Explanations of Physical Change, Molecular Models of Physical Change (strand A) Learning Progression
Level 3: Phase change and heating: Can explain that when a solid or liquid is heated, it occupies more volume because of the faster movements of molecules.
Level 2: Mixing of gases: Knows that, when two different gases are mixed, the molecules of the mix together at random. Compression of gases: Knows that when a volume of gas is compressed (or expanded), the molecules move closer together (or further apart) and are still distributed at random, but the molecules do not change their size or their mass. Phase change and heating: Knows that in phase changes, the molecules speed up - from solid to liquid and from liquid to gas.
Level 1: Compression of gases: Knows that when a gas is compressed (or expanded), the number of molecules in that gas does not change.
Level 0: Notions - naive conceptions.