C1.1 - Key Words

Atom

Smallest particle of an element. Atoms have a nucleus containing protons and (usually) neutrons, surrounded by electrons

Chemical change

Change that produces new substances

Chemical reaction

Process in which substances react to form different substances

Electrostatic forces

Forces of attraction or repulsion between electrically charged particles

Matter

Anything that has mass

Model

Description, analogy, or equation that helps you to explain the physical world

Particle

Tiny piece of matter, such as an atom, ion, or molecule

Particle model

Scientific idea used to explain the properties of solids, liquids and gases

Physical change

Change, such as changes in state, that does not result in new substances being made

State

The form that a substance has (solid, liquid, or gas) under given conditions of temperature and pressure