BMG Year 9 Core Chemistry

Element

A pure substance made up of only 1 type of atom

Compound

A compound contains 2 or more different types of atoms chemically bonded to each other

Atom

The smallest unit of matter

Molecule

A molecule contains two or more non-metal atoms covalently bonded together

Chemical Change 

A chemical change results from a chemical reaction. A new substance is formed.

Chemical Reactions

A chemical reaction always involves a rearrangement of atoms in the reactants to form a new product.

Law of Conservation Of Mass

Number of atoms in the reactants = Number of atoms in products

Ions

When the elements gain or lose electrons, they are known as IONS

Positive ions

Cations

Negative ions

How are ionic bonds formed

If electrons between elements are given and received

Polyatomic ions

Ions that contain more than 1 atom

compound

a substance made up of two or more different chemical elements combined in a fixed ratio

electron configuration

the arrangement of electrons in each
level around a nucleus

electrolysis

uses electricity to separate the metals and non-metals from a pure liquid compound into individual elements.

reduction

is done by heating the metal ore
in air (oxygen) and for some metals the addition of carbon (zinc and iron).