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colloid

(Encyclopedia)colloid kŏlˈoid [key] [Gr.,=gluelike], a mixture in which one substance is divided into minute particles (called colloidal particles) and dispersed throughout a second substance. The mixture is also...

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....

laser

(Encyclopedia)CE5 Ordinary light sources produce incoherent light, while a laser produces a beam of coherent light. laser [acronym for light amplification by stimulated emission of radiation], device for the cr...

water

(Encyclopedia)CE5 A. Water molecule (black circles represent valence-shell electrons) B. Structure of ice: Each oxygen atom (white circles) is bonded to four other oxygen atoms by hydrogen bonds, the hydrogen at...

acids and bases

(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...

coenzyme

(Encyclopedia)coenzyme kō-ĕnˈzīm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

quantum theory

(Encyclopedia)quantum theory, modern physical theory concerned with the emission and absorption of energy by matter and with the motion of material particles; the quantum theory and the theory of relativity togethe...

rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...

virus

(Encyclopedia)CE5 Structure of a tobacco mosaic virus, an RNA-containing virus virus, parasite with a noncellular structure composed mainly of nucleic acid within a protein coat. Most viruses are too small (100...

physics

(Encyclopedia)physics, branch of science traditionally defined as the study of matter, energy, and the relation between them; it was called natural philosophy until the late 19th cent. and is still known by this na...