From Wikipedia, the free encyclopedia. Acetic anhydride, or ethanoic anhydride, is the chemical compound with the formula (CH 3 CO) 2 O. Commonly abbreviated Ac 2 O, it is the simplest isolable anhydride of a carboxylic acid and is widely used as a reagent in organic synthesis.o a decreasing extent, acetic anhydride is also prepared by the reaction of ketene (ethenone) with acetic acid at 45â55 Â°C and low pressure (0.05â0.2 bar).
Definition: The prefix (eu-) means good, well, pleasant or true. It is derived from the Greek eu meaning well and eus meaning good. Eubacteria (eu-bacteria) - kingdom in the bacteria domain. Bacteria are considered to be true bacteria, distinguishing them from archaebacteria.
The unit of measurement to express the change in value between two currencies is called a âpip.â If EUR/USD moves from 1.2250 to 1.2251, that .0001 USD rise in value is ONE PIP. A pip is usually the last decimal place of a quotation.