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mercurous chloride

(Encyclopedia)mercurous chloride, mercury (I) chloride, or calomel, chemical compound, Hg2Cl2, a white crystalline powder, very slightly soluble in water. It was once used medicinally as a purgative, cathartic, li...

adenosine monophosphate

(Encyclopedia)adenosine monophosphate (AMP) ədĕnˈəsēn mŏnˌəfŏsˈfāt [key], organic compound composed of an adenine base, the sugar ribose, and one phosphate unit. AMP is one of the possible products of th...

hydrogen fluoride

(Encyclopedia)hydrogen fluoride, chemical compound, HF, a colorless, fuming liquid or colorless gas that boils at 19.54℃. It is miscible with water and is soluble in benzene, toluene, and concentrated sulfuric ac...

silica

(Encyclopedia)silica or silicon dioxide, chemical compound, SiO2. It is insoluble in water, slightly soluble in alkalies, and soluble in dilute hydrofluoric acid. Pure silica is colorless to white. It occurs in sev...

hardening

(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...

neutralization

(Encyclopedia)neutralization, chemical reaction, according to the Arrhenius theory of acids and bases, in which a water solution of acid is mixed with a water solution of base to form a salt and water; this reactio...

herbicide

(Encyclopedia)herbicide hrˈbəsīdˌ [key], chemical compound that kills plants or inhibits their normal growth. A herbicide in a particular formulation and application can be described as selective or nonselectiv...

Jaffna

(Encyclopedia)Jaffna jăfˈnə [key], peninsula, northernmost part of Sri Lanka, separated from India by Palk Strait. The peninsula is densely inhabited, largely by Tamil-speaking people. Jaffna suffered under the ...

element

(Encyclopedia)CE5 element, in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compound can be decomposed into its constituent elements by means o...

sulfonic acid

(Encyclopedia)sulfonic acid səlfŏnˈĭk [key], organic compound containing the functional group RSO2OH, which consists of a sulfur atom, S, bonded to a carbon atom that may be part of a large aliphatic or aromati...