As a model of the new system a prototype allows for several forms of communication. First, it allows the developers to communicate to the users their understanding of the requirements. (Obviously before a prototype can be built there must be some initial requirements discussions between developers and users).
(Arrhenius) a substance that yeilds hydroxide ions in an aqueous solution; metallic oxides in water. Buffers. substances that in solution are capable of neutralizing, within limits both acids and bases, and thereby maintaining the original or constant pH of the solution; substances that prevent changes in pH. Ex. borax, sodium phosphates, and citrates. Crystallization. the process by which a substance is given definite form.
Buffer solutions are solutions that resist changes in pH (by resisting changes in hydronium ion and hydroxide ion concentrations) upon addition of small amounts of acid or base, or upon dilution. They usually consist of a weak acid and its conjugate base, or, less commonly, a weak base and its conjugate acid.