Atoms and Elements

The number of protons that an atom contains.

one of the 4 basic forces in nature; the strongest of the four.

A table that visually organizes the similarities between all known elements.

a subatomic particle identical with the nucleus of the hydrogen atom; has a positive charge.

Particles that are smaller than an atom

A subatomic particle that is negatively charged & that occupies the energy levels in an atom.

An uncharged particle found in the nucleus of an atom.

The average mass of all the known isotopes of an element

An abbreviation that represents the name of an element; used in chemical formulas.

The electrons in an atom that are involved in the formation of chemical bonds.

A theory that states that ALL matter is composed on tiny particles called atoms.

A region around the nucleus of an atom where electrons are most likely found

Forms of the same element that have different numbers of neutrons and different mass numbers.

The total number of protons and neutrons in the nucleus of an atom.

The center core of an atom that contains protons and neutrons.