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.
On the other. hand, a weak acid such as acetic acid, CH. 3. COOH, only ionizes to a small extent, so both. the undissociated acid and its anion can exist in sufficient concentration in solution to. maintain constant pH. When the acetic acid-sodium acetate buffer is prepared the following equilibrium is. established.