Day 1 Key Vocabulary and Concepts

Nucleus

The center of an atom that contains the proton and neutrons and has a positive charge.

Compound

A chemical substance made up of 2 or more kinds of atoms bonded together.

Electron Shells

A collection of orbitals around the nucleus, each having its own energy level.

Mixture

A combination of two or more types of matter that retain their own individual properties.

Organic Compounds

A compound containing a chain of carbon atoms bound with other elements such as hydrogen and oxygen.

Neutron

A neutral subatomic particle located in the nucleus.

Proton

A positively charged subatomic particle located in the nucleus and has an atomic mass of 1.

Element

A pure substance containing only one type of atom.

Electron

A subatomic particle that has almost no mass and a negative charge.

Atomic Mass

The mass of an atom equal to the number of protons and neutrons.

Valence Electrons

The number of negatively charged particles in the most outer shell.

Atomic Number

The number of protons in the atoms of a particular element that is unique only to that element.

Chemical Change

The reaction between substances that results in new substances with different properties.

Reactivity

The tendency of an element to react with other elements to produce compounds.