When a chemical reaction occurs, atoms are neither created ... The other kind of change in chemistry is a physical change, which is when a substance changes without becoming a new chemical.

Melting and freezing are both physical changes ... of the word equation to show that a reaction has occurred. Chemical reactions happen all around us. When we burn methane in a Bunsen burner ...

Physical chemists are focused on understanding the physical properties of atoms and molecules, the way chemical reactions work, and what these properties reveal. Their discoveries are based on ...