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hydroxyl group

(Encyclopedia)hydroxyl group hīdrŏkˈsĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a single bond to a hydrogen atom. An alcohol is formed when a hydroxyl group is joined by ...

Harvard College Observatory

(Encyclopedia)Harvard College Observatory, astronomical observatory located in Cambridge, Mass., operated by Harvard (Harvard College at the time of the observatory's founding in 1839). Its equipment includes a 61-...

sulfate

(Encyclopedia)sulfate, chemical compound containing the sulfate (SO4) radical. Sulfates are salts or esters of sulfuric acid, H2SO4, formed by replacing one or both of the hydrogens with a metal (e.g., sodium) or a...

energy

(Encyclopedia)CE5 Relations between potential energy (PE) and kinetic energy (KE) for a swinging pendulum energy, in physics, the ability or capacity to do work or to produce change. Forms of energy include hea...

ligand

(Encyclopedia)ligand lĭgˈənd [key], charged or uncharged molecule with one or more unshared pairs of electrons that can attach to a central metallic atom or ion to form an aggregate known as a complex ion (see c...

aromatic compound

(Encyclopedia)aromatic compound, any of a large class of compounds that includes benzene and compounds that resemble benzene in certain of their chemical properties. Originally applied to a small class of pleasant-...

bail

(Encyclopedia)bail, in law, procurement of release from prison of a person awaiting trial or an appeal, by the deposit of security to insure his submission at the required time to legal authority. The monetary valu...

Fleming, Ian Lancaster

(Encyclopedia)Fleming, Ian Lancaster, 1908–64, English spy novelist, b. London. Son of a Conservative member of Parliament, Fleming was educated at Eton, Sandhurst, and Munich and Geneva universities and worked a...

Dodd, William

(Encyclopedia)Dodd, William, 1729–77, English author. At one time king's chaplain, he ran heavily into debt, forged a bond, and was sentenced to death. Dr. Johnson led a movement to obtain clemency, but Dodd was ...

oxidation and reduction

(Encyclopedia)oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation was used to re...