Journal 2

Decompostion reactions – are the opposite of composition reactions. one substance breaks down to form 2 or more new substances. For substances that break down to form 2 new substances, the general equation can be written: XY = X + Y
Example: calcium carbonate = calcium oxide + carbon dioxide.

Combustion reactions – is simply burning a substance in oxygen, so oxygen is always the reactant. The products will vary, depending on the substance that is burnt.
Examples of combustion reactions are: propane + oxygen = carbon dioxide + water.

In our next lesson we are going to doin a pracktical on these 2 forms of chemical reactions. After we do the practicals we are going to have do a pracktical report on the experiment.