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.
Bases are substances that can react with acids and neutralise them. Alkalis are bases that are soluble in water. The pH scale measures how acidic or alkaline a substance is. Substances with a pH lower than 7 are acidic, those with a pH of 7 are neutral and those with a pH greater than 7 are alkaline.he chemical properties of many solutions enable them to be divided into three categories-acids, alkalis and neutral solutions. The strength of the acidity or alkalinity is expressed by the pH scale. 1  solutions with a pH less than 7 are acidic.