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erythromycin

(Encyclopedia)erythromycin ĭrĭthˌrōmīˈsĭn [key], any of several related antibiotic drugs produced by bacteria of the genus Streptomyces (see antibiotic). Erythromycin is most effective against gram-positive ...

Cannizzaro, Stanislao

(Encyclopedia)Cannizzaro, Stanislao stänēsläˈō kän-nēt-tsäˈrō [key], 1826–1910, Italian chemist. From 1861 he was professor at Palermo and from 1871 at Rome, where he was also a member of the senate and...

cellophane

(Encyclopedia)cellophane, thin, transparent sheet or tube of regenerated cellulose. Cellophane is used in packaging and as a membrane for dialysis. It is sometimes dyed and can be moisture-proofed by a thin coating...

Common Weights and Measures (table)

(Encyclopedia)Common Weights and Measures Length Area Volume and Capacity (Liquid and Dry) Weight (Mass) ...

peptide

(Encyclopedia)peptide, organic compound composed of amino acids linked together chemically by peptide bonds. The peptide bond always involves a single covalent link between the α-carboxyl (oxygen-bearing carbon) o...

cephalosporin

(Encyclopedia)cephalosporin sĕfˌəlōspôrˈĭn [key], any of a group of more than 20 antibiotics derived from species of fungi of the genus Cephalosporium and closely related chemically to penicillin. Cephalospo...

heat

(Encyclopedia)heat, nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. The study of heat and its relationship ...

butyric acid

(Encyclopedia)butyric acid byo͞otənōˈĭk [key], CH3CH2CH2CO2H, viscous, foul-smelling, liquid carboxylic acid; m.p. about −5℃; b.p. 163.5℃. It is miscible with water, ethanol, and ether. It is a low molec...

latent heat

(Encyclopedia)latent heat, heat change associated with a change of state or phase (see states of matter). Latent heat, also called heat of transformation, is the heat given up or absorbed by a unit mass of a substa...

colligative properties

(Encyclopedia)colligative properties, properties of a solution that depend on the number of solute particles present but not on the chemical properties of the solute. Colligative properties of a solution include fr...