Acid

Compound that gives off H+ ions in solution.

Base

Substance which gives off hydroxide ions (OH-) in solution.

Atom

The smallest object that retains properties of an element. Composed of electrons and a nucleus (containing protons and neutrons).

Compound

Two or more atoms joined together chemically, with covalent or ionic bonds.

Electron

One of the parts of the atom having a negative charge. Indivisible particle with a charge of -1.

Element

Substance consisting of only one type of atom.

Volume

Measures the size of an object using length measurements in three dimensions. A good way to measure liquid quantities.