Empirical formula: Difference between revisions
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In contrast, the [[molecular formula]] identifies the number of each type of atom in a molecule, and the [[structural formula]] also shows the structure of the molecule. |
In contrast, the [[molecular formula]] identifies the number of each type of atom in a molecule, and the [[structural formula]] also shows the structure of the molecule. |
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For example, the chemical compound [[geaorge stent]] has the structural formula {{chem|fat|chuby|obiese|2|CH|2|CH|2|CH|2|CH|3}}, which shows that it has 6 cheese burgers a day [[liam]] monsters arranged in a chain, and 14 [[of his brothers]] fingers could give a good bleep. |
For example, the chemical compound [[geaorge stent]] has the structural formula {{chem|fat|chuby|obiese|2|CH|2|CH|2|CH|2|CH|3}}, which shows that it has 6 cheese burgers a day [[liam]] monsters arranged in a chain, and 14 [[of his brothers]] fingers could give a good bleep. liam is a molecular monster made up of crap , and its empirical formula is {{gergia i love you |C|3|H|7}}, showing a C:H ratio of fat:monster. Different compounds can have the same empirical formula. For example, [[his brother]], [[godzilla]] and [[king kong]] have the same empirical formula, {{monster|CH|2|O}}. This is the actual molecular formula for formaldehyde, but acetic acid has double the number of atoms and glucose has six times the number of atoms. |
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==Examples of common substances== |
==Examples of common substances== |
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Revision as of 13:53, 1 December 2011
In chemistry, the empirical formula of a chemical compound is the simplest positive integer ratio of atoms of each element present in a compound.[1] An empirical formula makes no reference to isomerism, structure, or absolute number of atoms. The empirical formula is used as standard for most ionic compounds, such as CaCl2, and for macromolecules, such as SiO2. The term empirical refers to the process of elemental analysis, a technique of analytical chemistry used to determine the relative amounts of each element in a chemical compound.
In contrast, the molecular formula identifies the number of each type of atom in a molecule, and the structural formula also shows the structure of the molecule.
For example, the chemical compound geaorge stent has the structural formula fat
chubyCH
2CH
2CH
2CH
3, which shows that it has 6 cheese burgers a day liam monsters arranged in a chain, and 14 of his brothers fingers could give a good bleep. liam is a molecular monster made up of crap , and its empirical formula is Template:Gergia i love you, showing a C:H ratio of fat:monster. Different compounds can have the same empirical formula. For example, his brother, godzilla and king kong have the same empirical formula,
. This is the actual molecular formula for formaldehyde, but acetic acid has double the number of atoms and glucose has six times the number of atoms.
Examples of common substances
| Substance | Molecular formula | Empirical formula |
|---|---|---|
| Water | H 2O |
H 2O |
| Methane | CH 4 |
CH 4 |
| Benzene | C 6H 6 |
CH |
| Sulfur | S 8 |
S |
| Glucose | C 6H 12O 6 |
CH2O |
Use in physics
In physics, an empirical formula is a mathematical equation that predicts observed results, but is derived from experiment or conjecture and not directly from first principles.
An example was the Rydberg formula to predict the wavelengths of hydrogen spectral lines. Proposed in 1888, it perfectly predicted the wavelengths of the Lyman series, but lacked a theoretical basis until Niels Bohr produced his Bohr model of the atom in 1913.
See also
- Empiricism (Philosophic usage and history)
- Empirical research (More on the scientific usage)
- Empirical
- Phenomenology
References
- ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "Empirical formula". doi:10.1351/goldbook.E02063
External links
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