Atoms and Subatomic Particles

Flashcards for Atoms and Subatomic Particles

Matter

Anything that occupies space and has mass.

Atoms

The smallest units of matter that still maintain the properties of an element.

Element

A substance that cannot be broken down further.

Atomic Number

The number of protons in an atom.

Atomic Mass

The number of protons and neutrons in an atom's nucleus.

Subatomic Particles

Protons, neutrons, and electrons.

Protons (p+)

Positively charged particles found in the nucleus of an atom.

Neutrons (n)

Neutral particles found in the nucleus of an atom.

Electrons (e-)

Negatively charged particles that orbit the nucleus of an atom.

Valence Shell

The outermost electron shell of an atom.

Electrical Force

Atoms are held together because opposite charges attract.

Full Valence Shell

Non-reactive and stable.

Many Open Spaces in Valence Shell

Reactive and unstable - wants to fill valence shell.