3) In hardware design, a prototype is a hand-built model that represents a manufactured (easily replicable) product sufficiently for designers to visualize and test the design. The word prototype comes from the Latin words proto, meaning original, and typus, meaning form or model.
In chemistry, a salt is an ionic compound which is made up of two groups of oppositely charged ions. The ion with a positive charge is called a cation, and the one with a negative charge is called an anion.
double salt. n. A salt or mineral, such as alum or dolomite, that has more than one type of cation or anion and forms when a solution of two simpler salts undergoes crystallization. double salt. n. (Chemistry) a solid solution of two simple salts formed by crystallizing a solution of the two salts. Compare complex salt.