The general term is "chemical reaction". There are sub-categories like "oxidation-reduction", "double (and single) replacement", and others.
Reactants.
They are reactants.
a chemist
the name given to chemicals which react together is products
it`s a precipitate
compound
Reactants (can't be any more simple now can it?)
They are reactants.
They are called monomers.
The are called PRODUCTS.
Hydrocarbons
There are advantages and disadvantages to storing in alphabetical order. Generally you want to segregate chemicals according to type rather than name. Acids and bases usually should not be stored together. Oxidizers and combustibles should not be stored together. You get the idea; in general - don't store chemicals together with other chemicals that they will react with violently. If you store strictly alphabetically you could wind up with acetic acid being stored with ammonia - which I do not think you would want to do. Once the chemicals are segregated according to incompatibility, it might be good to organize by alphabetical order so that someone looking for a particular chemical can find it more easily.