empirical formula

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formula

 [for´mu-lah] (pl. formulas, for´mulae) (L.)
1. an expression, using numbers or symbols, giving the directions for preparing a compound (such as a medicine) or giving a procedure to follow to obtain a desired result.
2. a mixture for feeding an infant, usually with cow's milk as a base, supplemented with vitamins and minerals. Various formulas are available, differing in protein, fat, and carbohydrate content in order to meet the nutritional requirements or restrictions of individual infants.
chemical formula a combination of symbols used to express the chemical components of a substance.
empirical formula a chemical formula that expresses the proportions of the elements present in a substance.
molecular formula a chemical formula expressing the number of each element present in a substance, without indicating how they are linked.
spatial formula (stereochemical formula) a chemical formula giving the numbers of atoms of each element present in a molecule of a substance, which atom is linked to which, the types of linkages involved, and the relative positions of the atoms in space.
structural formula a chemical formula showing the spatial arrangement of the atoms and the linkage of every atom.

empirical formula

a chemical formula that shows the smallest whole number ratio of atoms of different elements in a molecule. It does not indicate structural linkage. An example is CH2O, a carbohydrate.

empirical formula (em·piˑ·r·kl fōrˑ·myōō·l),

n the simplest whole-number formula used to express the composition of a chemical compound.

formula

pl. formulae, formulas [L.] an expression, using numbers or symbols, of the composition of, or of directions for preparing, a compound, such as a medicine, or of a procedure to follow to obtain a desired result, or of a single concept.

chemical formula
a combination of symbols used to express the chemical components of a substance.
dental formula
see dental formula.
empirical formula
a chemical formula that expresses the proportions of the elements present in a substance.
gait formula
sets out the times that the feet are individually in contact with the ground while the animal is moving.
molecular formula
a chemical formula expressing the number of atoms of each element present in a substance, without indicating how they are linked.
spatial formula, stereochemical formula
a chemical formula giving the numbers of atoms of each element present in a molecule of a substance, which atom is linked to which, the types of linkages involved, and the relative positions of the atoms in space.
structural formula
a chemical formula showing the spatial arrangement of the atoms and the linkage of every atom.
vertebral formula
sets out the number of vertebrae in each of the sections of the spinal column.
References in periodicals archive ?
The results support the proposition that a star's chemical composition and the nature of its planetary system are linked.
Chemical composition limits of the values for the sudird thin steel sheets are presented in Table 1 and the parameters determined in the tests are noted in Table 2.
And so science seems to be succeeding in studying not only the chemical composition of a star, but also the mineralogical structure of a never-seen planet.
Spectrometer--An instrument that measures wavelengths of light spectra to determine the chemical composition of an item.
Regardless of the Q-Cert designation level, all Lincoln consumables are manufactured under Chemical Composition Control and Six Sigma as well as ISO 9001 standards.
2004) highlighted the chemical, physical, and biological differences between two widely used DEP samples, one mainly studied for pulmonary toxicity and the other for genotoxicity; before their studies, the chemical composition and biologic activity of the samples had not been compared.
The detailed pages on each gem considered are not organized alphabetically but are classified by chemical composition from carbon (diamonds) through oxides (including sapphires) to organics (pearls).
Two of the most critical factors in developing the product were the chemical composition and the heat treatment of the pipe.
has been granted a patent for a non-toxic chemical composition that inhibits corrosion in metal substrates.
After separation, MALDI-TOF mass spectrometry was used to identify the exact chemical composition of the end groups, and to correlate molecular size with molecular mass.
Improvements to the lab included $3 million in new equipment that can identify narcotic samples and pinpoint the chemical composition of poisons.
To identify the rock as a mineral, Cressey had to prove that the specimen was: naturally occurring; inorganic (nonliving); and a solid with a distinct chemical composition and crystal structure.