equivalent (e-kwiv'al-ent)

Of equal value; as a n., an e. number, a term formerly used for the amount by weight of an element which was capable of combining with i part by weight of hydrogen. Thus, the e. of oxygen was 8, because 8 parts of this element unite with i part of hydrogen to form water. The term, however, is now applied to the amount by weight of any element which can replace i part by weight of hydrogen in a compound. It is equal to the atomic weight of the element divided by the number representing its quantivalence. endosmotic e. The ratio obtained by dividing the quantity of the replacing liquid in osmotic action by the quantity replaced. osmotic e. The ratio between the diffusive powers of liquids or gases. [Lat., aequivalare, to be worth the same.]