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vermilion

(Encyclopedia)vermilion, vivid red pigment of durable quality. It is a chemical compound of mercury and sulfur and is known as red sulfide of mercury; it was formerly obtained by grinding pure cinnabar but is now c...

mixture

(Encyclopedia)mixture, in chemistry, a physical combination of two or more pure substances (i.e., elements or compounds). A mixture is distinguished from a compound, which is formed by the chemical combination of t...

carbonyl group

(Encyclopedia)carbonyl group kärˈbənĭl [key], in chemistry, functional group that consists of an oxygen atom joined by a double bond to a carbon atom. The carbon atom is joined to the remainder of the molecule ...

carbonate

(Encyclopedia)carbonate kärˈbənātˌ, –nət [key], chemical compound containing the carbonate radical or ion, CO3−2. Most familiar carbonates are salts that are formed by reacting an inorganic base (e.g., a ...

electrolysis

(Encyclopedia)CE5 Electrolysis: In a typical reaction electrodes are placed in a solution of hydrogen chloride, HCl, which contains both hydrogen and chlorine ions. The battery removes electrons from the anode, ...

mustard gas

(Encyclopedia)mustard gas, chemical compound used as a poison gas in World War I. The burning sensation it causes on contact with the skin is similar to that caused by oil from black mustard seeds. The compound is ...

sodium thiosulfate

(Encyclopedia)sodium thiosulfate, Na2S2O3, colorless crystalline compound that is more familiar as the pentahydrate, Na2S2O3·5H2O, an efflorescent, monoclinic crystalline substance also called sodium hyposulfite o...

silica gel

(Encyclopedia)silica gel, chemical compound. It is a colloidal form of silica, and usually resembles coarse white sand. It may be prepared by partial dehydration of metasilicic acid, H2SiO3. Because it has many tin...

common-ion effect

(Encyclopedia)common-ion effect, decrease in solubility of an ionic salt, i.e., one that dissociates in solution into its ions, caused by the presence in solution of another solute that contains one of the same ion...

hydrogen sulfide

(Encyclopedia)hydrogen sulfide, chemical compound, H2S, a colorless, extremely poisonous gas that has a very disagreeable odor, much like that of rotten eggs. It is slightly soluble in water and is soluble in carbo...