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Chemical formula: C 6 H 9 N 3 O 2 ... ^a EINECS number 200-745-3 (D-histidine) ^a EINECS number 206-513-8 (L-histidine) ^a CID 71083 from PubChem (D-histidine)
Histidine (symbol His or H) [2] is an essential amino acid that is used in the biosynthesis of proteins.It contains an α-amino group (which is in the protonated –NH 3 + form under biological conditions), a carboxylic acid group (which is in the deprotonated –COO − form under biological conditions), and an imidazole side chain (which is partially protonated), classifying it as a ...
This is a list of CAS numbers by chemical formulas and chemical compounds, indexed by formula.The CAS number is a unique number applied to a specific chemical by the Chemical Abstracts Service (CAS).This list complements alternative listings to be found at list of inorganic compounds and glossary of chemical formulae
Chemical formula Synonyms CAS number CAgO carbonylsilver: CCl 2 F 2: dichlorodifluoromethane freon-12: 75-71-8 CCl 4: carbon tetrachloride tetrachloromethane: 56-23-5 C(CN) 4: tetracyanomethane: 24331-09-7 CFCl 3: trichlorofluoromethane freon-11: 75-69-4 CFCl 2 CF 2 Cl: chlorotrifluoromethane freon-13: 75-72-9 CHCl 3: chloroform ...
The numbers 200-900 would be confused easily with 22 to 29 if they were used in chemistry. khīlioi = 1000, diskhīlioi = 2000, triskhīlioi = 3000, etc. 13 to 19 are formed by starting with the Greek word for the number of ones, followed by και (the Greek word for 'and'), followed by δέκα (the Greek word for 'ten').
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
In chemistry, a number of prefixes, suffixes and infixes are used to describe the type and position of the functional groups in the compound. The steps for naming an organic compound are: [5] Identification of the most senior group. If more than one functional group, if any, is present, the one with highest group precedence should be used.
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as parentheses, dashes, brackets, commas and plus (+) and minus (−) signs.