Elements, compounds and mixtures

What does an element consist of?

Only one type of atom

What is a diatomic molecule?

A molecule with two atoms in it

What is a compound?

A compound is a substance that is made of two or more different elements which are chemically bonded in a fixed ratio

What is an example of a compound?

Carbon dioxide - CO2

Is it easy to separate two original elements in a compound out again?

No - very difficult

What are the properties of a compound usually like compared to the original elements?

Often totally differnet

Are mixtures easily separated?

Yes

What are the properties of a mixture like?

The properties of the separate parts

E.g. mixture of iron powder and sulfur powder will show the properties of both iron and sulfur

Is a mixture a pure substance?

No

What is a pure substance?

Completely made up of a single element or compound

How can you tell a substance is pure?

Has a specific melting and boiling point

How will a mixture melt?

Gradually over a range of temperatures