COMPOUNDS AND MIXTURES

Particle diagrams can be used to represent atoms. Each circle represents an atom, and circles of different sizes or colours are used to represent different elements.

Diagram A represents . . .

• unbonded atoms of one element.

• molecules of one element.

Diagram B represents . . .

• unbonded atoms of one element.

• molecules of one element.

The photograph represents . . .

• unbonded atoms of one element.

• molecules of one element.

• atoms of a compound.

• molecules of a compound.

The photograph represents . . .

• unbonded atoms of one element.

• molecules of one element.

• unbonded atoms of two elements.

• molecules of two different elements.

An atom is . . .

• the smallest unit of matter.

• formed when two or more atoms are chemically bonded together.

• formed when atoms of two or more elements are chemically bonded together.

Elements are . . .

• pure substances formed from one type of atom only.

• formed when two or more atoms are chemically bonded together.

• formed when atoms of two or more elements are chemically bonded together.

Molecules are . . .

• pure substances formed from one type of atom only.

• the smallest units of matter.

• formed when two or more atoms are chemically bonded together.

Compounds are . . .

• pure substances formed from one type of atom only.

• the smallest units of matter.

• formed when atoms of two or more elements are chemically bonded together.

Mixtures are . . .

• pure substances formed from one type of atom only.

• formed from two or more substances, mixed together without forming chemical bonds.

• formed when two or more atoms are chemically bonded together.

True or false? Molecules are formed when two or more atoms are chemically bonded together.

• true

• false