Demystified Videos In Demystified, Britannica has all the answers to your burning questions.This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find.Britannica Classics Check out these retro videos from Encyclopedia Britannica’s archives.Britannica Explains In these videos, Britannica explains a variety of topics and answers frequently asked questions.A Guide to IUPAC Nomenclature of Organic Compounds 1993.
with the Greek for "and"inserted (as in triskaidekaphobia). khīlioi = 1000, diskhīlioi = 2000, triskhīlioi = 3000, etc., and 13 to 19 are treiskaideka etc. The numbers 200-900 would be confused easily with 22 to 29 if they were used in chemistry. In Ancient Greek, hekaton = 100, diakosioi = 200, triakosioi = 300, etc. The forms 100 and upwards are not correct Greek. The others are derived from Greek numbers. Multiplicative prefixes for naming assemblies of identical units NumberĪnd/or "deka" is replaced with "deci". Numerical prefixes for multiplication of compound or complex (as in complicated) features are created by adding kis to the basic numerical prefix, with the exception of numbers 2 and 3, which are bis- and tris-, respectively. Numerical terms for compound or complex features There are two more types of numerical prefixes in IUPAC organic chemistry nomenclature. However both the Chemical Abstracts Service and the Beilstein database use the alternative spelling eicosa. IUPAC prefers the spelling icosa- for the affix corresponding to the number twenty on the grounds of etymology. In compound affixes, the numeral two is represented by do- except when it forms part of the numbers 20 ( icosa-), 200 ( dicta-) or 2000 ( dilia-). In forming compound affixes, the numeral one is represented by the term hen- except when it forms part of the number eleven ( undeca-): henceĢ41 → hen- ( 1) + tetraconta- ( 40) + dicta- ( 200) = hentetracontadicta- 411 → undeca- ( 11) + tetracta- ( 400) = undecatetracta- The numeral two While the use of the affix mono- is rarely necessary in organic chemistry, it is often essential in inorganic chemistry to avoid ambiguity: carbon oxide could refer to either carbon monoxide or carbon dioxide. For example:ĥ48 → octa- ( 8) + tetraconta- ( 40) + pentacta- ( 500) = octatetracontapentacta- 9267 → hepta- ( 7) + hexaconta- ( 60) + dicta- ( 200) + nonalia- ( 9000) = heptahexacontadictanonalia- The numeral one The prefixes are given from the least significant decimal digit up: units, then tens, then hundreds, then thousands. The affixes are derived from both Latin and Greek.
The numerical multiplier (or multiplying affix) in IUPAC nomenclature indicates how many particular atoms or functional groups are attached at a particular point in a molecule.
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