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.
References in periodicals archive ?
Chemical composition and seasonal variations of rosemary oil from Southern Spain.
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.
FTIR analysis is a quick technique that enables the chemist to classify the chemical composition of each layer in the paint sample.
Remelt Secondary Ingot (RSI)--Aluminum scrap that is recycled into an intermediate 3roduct without a specific chemical composition. Independent fabricators and companies that melt scrap or dross to produce RSI or molten metal that is used in their plants for direct processing or sold in the market commonly use this technique.
We also determined the mineralogical and chemical composition and particle electrostatic charge.
The austenitizing temperature is a function of the chemical composition of the iron.
Both high school and college collections strong in chemistry will want to add this helpful analysis to their collection: over 100 groups of products receive attention to not only chemical composition, but historic product use, functions, and related issues.
Coconut Cures describes why coconut water can be used and useful as an IV solution for sick patients because it has a chemical composition similar to human plasma and therefore injected directly into the blood stream while be a rich source of vitamins and minerals.
If Eve knew the seed structure and chemical composition of the apple, would she still get a thrill out of biting it?
(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.