Name two methods that can be used to break down compounds into simpler substance

The two methods that can be used do break down compounds into simpler substances or smaller units, are known as Hydrolysis and Photolysis. 

Hydrolysis uses water to split a molecule. Water is used to break the bonds of a molecule. There are three main types of hydrolysis:1. acid hydrolysis2. base hydrolysis 3. salt hydrolysis

Photolysis uses energy from light to split molecules.  This energy is called photons. As in hydrolysis, photons are used to break the bonds of a molecule. Photolysis is a chemical reaction. 

Ibelieve your answer is true 

Ions gain or lose electrons