Chemistry Keywords

An atom

the smallest part of an element that still has properties of that element

Compound

2 or more different elements chemically combined

Energy level

The fixed energy value an electron in an atom may have

Atomic number

The number of protons in the nucleus of an atom of that element

Mass number

The number of protons and neutrons in the nucleus of an atom of that element

Isotopes

atoms of that same element with the same number of protons but a different number of neutrons

Ions

an atom that has lost or gained electrons. a charged atom

Molecule

two or more atoms chemically combined

Relative Atomic Mass

the average mass of all isotopes of an element, as they occur naturally, taking their abundances into account, relative to one twelfth the mass of a carbon-12 atom

Element

a substance that cannot be split up into simpler substances by chemical means