Atomic Structure and the Periodic Table

These flashcards cover key vocabulary and concepts related to atomic structure and the periodic table.

Atom

The smallest particle of an element that has the chemical properties of that element.

Sub-atomic particles

Particles that are smaller than an atom, including protons, neutrons, and electrons.

Proton

A positively charged sub-atomic particle found in the nucleus of an atom.

Neutron

A sub-atomic particle with no overall charge, found in the nucleus of an atom.

Electron

A negatively charged sub-atomic particle that moves in energy levels around the nucleus of an atom.

Nucleus

The center of an atom where protons and neutrons are found.

Electron shells

Energy levels in which electrons move around the nucleus.

Valence electrons

Electrons in the outermost shell of an atom, involved in bonding.

Proton number (atomic number)

The total number of protons in the nucleus of an atom, which identifies the element.

Nucleon number (mass number)

The total number of protons and neutrons in the nucleus.

Isotope

Atoms of the same element with different numbers of neutrons, resulting in different masses.

Radioisotope

An isotope that is radioactive and emits radiation as it decays.

Noble gas

An unreactive gaseous element with a filled outer electron shell.

Valency number

The number of electrons an atom can lose or gain to reach a noble gas configuration.

Mass spectrometer

An instrument used to measure the natural abundances of isotopes.

Electrically neutral

An atom that has no overall charge due to equal numbers of protons and electrons.