KS3+Year+7+Bang,+Bubbles+and+Burning


 * Bang, Bubbles & Burning**

Chemical reaction - when 2 substances join together ( ro break apart) to make a new substance. Observation - what we see when we carefully look at a reaction Reversible (irreversible) - when a reaction can go back so hat we start with the first chemicals. Irreversible reactions cannot go back to the start Physical change - when water turns to ice there is no chemical reaction, it is a physical change.
 * New Words**

Hoffman Voltameter