isotope

Atoms of the same element with different numbers of neutrons

A pure substance made of only one type of atom

Element

A substance made of two or more elements chemically bonded

compound

A mixture that is uniform in composition

Homogeneous mixture

A mixture that is not uniform and has distinct parts

Heterogeneous mixture

A homogeneous mixture where one substance (solute) is dissolved in another (solvent.

Solution

The substance being dissolved in a solution

Solute

The substance doing the dissolving in a solution

Solvent

A solution that can still dissolve more solute as a given temperature

Unsaturated

A solution that contains the maximum amount of solute it can hold at a given temperature

Saturated

A solution that contains more solute than it normally can at a given temperature

Supersaturated

Different forms of the same element with different structures

Allotrope

Elements that are usually shiny, good conductors, malleable, and ductile

Metal

Elements that are poor conductors, brittle if solid, and not shiny

Nonmetals

A chemical bond formed by the sharing of electrons between atoms

Covalent bond

A covalent bond where electrons are shaped unequally, creating partial charges

Polar covalent bond

A chemical bond formed when electrons are transferred from one atom to another

Ionic bond

Substances that start a chemical reaction

Reactants

Substances formed at the end of a chemical reaction

Products

Mass is neither created nor destroyed in a chemical reaction

Law of Conservations of Mass

The minimum energy needed to start a chemical reaction

Activation energy

A reaction that releases energy (using as heat)

Exothermic

A reaction that absorbs energy (usually as heat)

Endothermic

A substance that speeds up a reaction without being consumed

Catalyst

A biological catalyst that speeds up chemical reactions in living things

Enzyme

6.022 x 10^23 the number of particles in one mole of a substance

Avogadros number

Equals the number of protons and electrons in a neutral atom

Atomic number

Atomic number

Protons