Front

Building block of matter

Back

Atom

Front

Compound

Back

Pure substance formed when different elements combine.

Front

Proton

Back

Positively charged particle in an atom's nucleus.

Front

Molecule

Back

Compound with atoms held by covalent bonds.

Front

Attractive forces between molecules.

Back

van der Waals force

Front

Process of atom reorganization in substances.

Back

Chemical reaction

Front

Starting substances in a chemical reaction

Back

reactant

Front

Enzyme

Back

Special proteins that are biological catalysts.

Front

Molecules with uneven charge distribution and oppositely charged regions.

Back

Polar molecule

Front

A substance that dissolves another (e.g., water)

Back

solvent