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salt, chemical compound

(Encyclopedia)salt, chemical compound (other than water) formed by a chemical reaction between an acid and a base (see acids and bases). Salts are also prepared by methods other than neutralization. A metal can c...

aldosterone

(Encyclopedia)aldosterone ălˌdōstĭrōnˈ [key], steroid secreted by the cortex of the adrenal gland. It is the most potent hormone regulating the body's electrolyte balance. Aldosterone acts directly on the kid...

dissociation

(Encyclopedia)dissociation, in chemistry, separation of a substance into atoms or ions. Thermal dissociation occurs at high temperatures. For example, hydrogen molecules (H2) dissociate into atoms (H) at very high ...

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...

Ion, in Greek mythology

(Encyclopedia)Ion: see Creusa (1.)

diffusion

(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...

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...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

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...

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....