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  2. Numeral prefix - Wikipedia

    en.wikipedia.org/wiki/Numeral_prefix

    The IUPAC nomenclature of organic chemistry, for example, uses the numerical prefixes derived from Greek, except for the prefix for 9 (as mentioned) and the prefixes from 1 to 4 (meth-, eth-, prop-, and but-), which are not derived from words for numbers. These prefixes were invented by the IUPAC, deriving them from the pre-existing names for ...

  3. IUPAC nomenclature of organic chemistry - Wikipedia

    en.wikipedia.org/wiki/IUPAC_nomenclature_of...

    Wherever it says "with numbers", it is understood that between the word and the numbers, the prefix (di-, tri-) is used. Adding of punctuation: Commas are put between numbers (2 5 5 becomes 2,5,5) Hyphens are put between a number and a letter (2 5 5 trimethylheptane becomes 2,5,5-trimethylheptane)

  4. Chemical nomenclature - Wikipedia

    en.wikipedia.org/wiki/Chemical_nomenclature

    Thus, NCl 3 is termed nitrogen trichloride, BF 3 is termed boron trifluoride, and P 2 O 5 is termed diphosphorus pentoxide (although the a of the prefix penta-should actually not be omitted before a vowel: the IUPAC Red Book 2005 page 69 states, "The final vowels of multiplicative prefixes should not be elided (although "monoxide", rather than ...

  5. List of country calling codes - Wikipedia

    en.wikipedia.org/wiki/List_of_country_calling_codes

    NANP members are assigned three-digit numbering plan area (NPA) codes under the common country prefix 1, shown in the format 1 (NPA). 1 North American Numbering Plan; 1 – United States, including United States territories: 1 (340) – United States Virgin Islands; 1 (670) – Northern Mariana Islands; 1 (671) – Guam; 1 (684) – American Samoa

  6. Metric prefix - Wikipedia

    en.wikipedia.org/wiki/Metric_prefix

    The prefixes from tera-to quetta-are based on the Ancient Greek or Ancient Latin numbers from 4 ... It is common to apply metric prefixes to the gram calorie, but not ...

  7. Telephone exchange names - Wikipedia

    en.wikipedia.org/wiki/Telephone_exchange_names

    Telephone numbers listed in 1920 in New York City having three-letter exchange prefixes. In the United States, the most-populous cities, such as New York City, Philadelphia, Boston, and Chicago, initially implemented dial service with telephone numbers consisting of three letters and four digits (3L-4N) according to a system developed by W. G. Blauvelt of AT&T in 1917. [1]

  8. List of pharmaceutical compound number prefixes - Wikipedia

    en.wikipedia.org/wiki/List_of_pharmaceutical...

    This list of pharmaceutical compound number prefixes provides codes used by individual pharmaceutical companies when naming their pharmaceutical drug candidates. . Pharmaceutical companies generally produce large numbers of compounds in the research phase for which it is impractical to use often long and cumbersome systematic chemical names, and for which the effort to generate nonproprietary ...

  9. Telephone prefix - Wikipedia

    en.wikipedia.org/wiki/Telephone_prefix

    A telephone prefix is the first set of digits after the country, and area codes of a telephone number.In the North American Numbering Plan countries (country code 1), it is the first three digits of a seven-digit local phone number, the second three digits of the 3-3-4 scheme.