FORMULA

formula. Formula, n. a prescribed or general form

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For″mu‐la (?), n.; pl. E. Formulas (#), L. Formulæ (#). [[L., dim. of forma form, model. SeeForm, n.]] 1. 1. A prescribed or set form; an established rule; a fixed or conventional method in which anything is to be done, arranged, or said.
2. 2. (Eccl.) A written confession of faith; a formal statement of foctrines.
3. 3. (Math.) A rule or principle expressed in algebraic language; as, the binominal formula.
4. 4. (Med.) A prescription or recipe for the preparation of a medicinal compound.
5. 5. (Chem.) A symbolic expression (by means of letters, figures, etc.) of the constituents or constitution of a compound.
☞ Chemical formulæ consist of the abbreviations of the names of the elements, with a small figure at the lower right hand, to denote the number of atoms of each element contained. Empirical formula (Chem.), an expression which gives the simple proportion of the constituents; as, the empirical formula of acetic acid is C2H4O2. — Graphic formula, Rational formula (Chem.), an expression of the constitution, and in a limited sense of the structure, of a compound, by the grouping of its atoms or radicals; as, a rational formula of acetic acid is CH3.(C:O).OH; — called also structural formula, constitutional formula, etc. See also the formula of Benzene nucleus, under Benzene. — Molecular formula (Chem.), a formula indicating the supposed molecular constitution of a compound.