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formula, in chemistry

(Encyclopedia)formula, in chemistry, an expression showing the chemical composition of a compound. Formulas of compounds are used in writing the equations (see chemical equations) that represent chemical reactions....

love-in-a-mist

(Encyclopedia)love-in-a-mist, hardy annual garden plant (Nigella damascena) of the family Ranunculaceae (buttercup family), having finely cut foliage and blue or white flowers surrounded by a cluster of thready bra...

teleportation, in physics

(Encyclopedia)teleportation, in physics, the transfer of key properties from one particle (or group of particles) to another a significant distance apart without a physical connection between the two particles (or ...

iris, in botany

(Encyclopedia)CE5 Red iris, Iris fulva iris, common name for members of the genus Iris of the Iridaceae, a family of perennial herbs that includes the crocuses, freesias, and gladioli. The family is characteriz...

python, in zoology

(Encyclopedia)python pīˈthŏn [key], name for nonvenomous constrictor snakes of the boa family, found in the tropical regions of Africa, Asia, Australia, and the S Pacific islands. Pythons climb and swim expertly...

mole, in chemistry

(Encyclopedia)mole, in chemistry, a quantity of particles of any type equal to Avogadro's number, or 6.02×1023 particles. One gram-molecular weight of any molecular substance contains exactly one mole of molecules...

depression, in psychiatry

(Encyclopedia)depression, in psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection. The two major types of mood disorder are unipolar disord...

proof, in printing

(Encyclopedia)proof, in printing, a trial impression for inspection. Proofreading is the inspection and marking of proof for correction of errors and imperfections. Proofreaders' marks are included in dictionaries....

conjunction, in astronomy

(Encyclopedia)conjunction, in astronomy, alignment of two celestial bodies as seen from the earth. Conjunction of the moon and the planets is often determined by reference to the sun. When a body is in conjunction ...

potassium nitrate

(Encyclopedia)potassium nitrate, chemical compound, KNO3, occurring as colorless, prismatic crystals or as a white powder; it is found pure in nature as the mineral saltpeter, or niter. (The name saltpeter is also ...