Answer the following question:
Answer variants:
Can be broken down into simpler substances by chemical reactions
A pure substance formed when two or more elements combine chemically in a fixed ratio
Iron, oxygen, and gold
Contains only one kind of atom
Has its own unique properties
Iron oxide, hydrogen sulphide, and sucrose
Distinguish between elements and compounds. 
 
i. Elements: 
 
 
 
Example:
 
ii. Compounds:
 
 
 
Example: