Atom Structure and Periodic Table Review

This set of flashcards covers fundamental vocabulary related to atomic structure and the periodic table, enabling review and study for chemistry concepts.

Atom

The smallest unit of matter that retains all of the chemical properties of an element.

Subatomic particles

Particles smaller than an atom, specifically protons, neutrons, and electrons.

Nucleus

The center of an atom that contains protons and neutrons.

Atomic number

The number of protons in an atom, which appears on the periodic table.

Cation

A positively charged ion that is formed by losing one or more electrons.

Anion

A negatively charged ion that is formed by gaining one or more electrons.

Periodic Law

A law stating that elements, when listed in order of their atomic numbers, fall into groups with similar properties.

Electron configuration

A shorthand description of the arrangement of electrons in an atom.

Valence electrons

Electrons in the highest-numbered shell of an atom.

Core electrons

Electrons in a lower-numbered shell of an atom.

Atomic mass unit (amu)

A unit of mass used to measure atoms, one-twelfth the mass of a carbon-12 atom.

Quantum mechanics

The modern theory that describes electron behavior, stating energies of electrons are quantized.

Shells

Groupings of electrons within an atom based on their energy levels.

Subshells

Grouping of electrons within a shell, each with a different maximum number of electrons.

Ionization energy (IE)

The amount of energy required to remove an electron from an atom in the gas phase.

Electron affinity (EA)

The change in energy when an electron is added to a neutral atom.