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equivalent weight

(Encyclopedia)equivalent weight. The equivalent weight of an element or radical is equal to its atomic weight or formula weight divided by the valence it assumes in compounds. The unit of equivalent weight is the a...

oxide

(Encyclopedia)oxide, chemical compound containing oxygen and one other chemical element. Oxides are widely and abundantly distributed in nature. Water is the oxide of hydrogen. Silicon dioxide is the major componen...

ozone

(Encyclopedia)ozone ōˈzōn [key], an allotropic form of the chemical element oxygen (see allotropy). Pure ozone is an unstable, faintly bluish gas with a characteristic fresh, penetrating odor. The gas has a dens...

asphyxia

(Encyclopedia)asphyxia ăsfĭkˈsēə [key], deficiency of oxygen and excess of carbon dioxide in the blood and body tissues. Asphyxia, often referred to as suffocation, usually results from an interruption of brea...

carbon monoxide

(Encyclopedia)carbon monoxide, chemical compound, CO, a colorless, odorless, tasteless, extremely poisonous gas that is less dense than air under ordinary conditions. It is very slightly soluble in water and burns ...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

chemical equation

(Encyclopedia)chemical equation, group of symbols representing a chemical reaction. There are a number of other symbols used in chemical equations. A symbol written above or below the reaction arrow indicates spe...

law of simple multiple proportions

(Encyclopedia)law of simple multiple proportions, in chemistry, the statement that when two or more elements form more than one compound, the ratio of the weights of one element that combine with a given weight of ...

Ratcliffe, Sir Peter John

(Encyclopedia)Ratcliffe, Sir Peter John, 1954–, British cellular and molecular biologist, M.D., Cambridge, 1987. He has been a researcher at Oxford since 1987. Ratcliffe, along with William Kaelin and Gregg Semen...

liquid air

(Encyclopedia)liquid air, ordinary air that has been liquefied by compression and cooling to extremely low temperatures (see liquefaction). Its commercial preparation involves purification by washing to remove solu...