Chemistry: Elements and Atomic Variations

Vocabulary terms based on lecture notes regarding the properties of elements, specific characteristics of Hydrogen and Helium, and differences between ions and isotopes.

Element

A pure substance containing only one type of atom.

Differentiation of Elements

Each element is distinguished from another by the number of protons it possesses in its nucleus.

Hydrogen

The smallest element, containing $1$ proton and $1$ electron, which is flammable, explosive, and found in water ($H_2O$).

Helium

A stable, non-flammable gas with $2$ protons and $2$ electrons that is a non-renewable resource and turns liquid at $-452^{\circ} F$.

Ions

Charged atoms that occur because the number of electrons is different from the number of protons; they can gain or lose electrons.

Isotopes

Atoms where the nucleus contains a non-regular number of neutrons, often making them radioactive.

Methane ($CH_4$)

A substance mentioned in the context of Carbon variations.

Atomic Variations

The possibility for the number of neutrons and electrons to vary without changing the identity of the element.