Soluble - The term soluble means that
a
substance dissolves.
An aqueous solution is soluble. If one mixes two
solutions together and no precipitate
forms, then
only the ions are
in solution. Thus, there is no reaction.
Note: Sometimes two solutions are mixed together, a reaction
can occur that does not form a
precipitate.
Usually when this type of reaction takes place,
there is a marked
color change when the product is formed or a large
temperature change is observed.
Insoluble - The term insoluble means a
substance does not dissolve.
Precipitate – A solid
beneath a liquid. If one
mixes two solutions and a solid forms,
this is called
a
precipitation reaction.