In this site we focused on the the areas of science incluod analytical chemisty, general chemistry, inorganic chemistry, organic chemistry, physical chemistry, and spectroscopy.(Online Chemistry Dictionary )

Yalla Science on Facebook

Blog Archive

Follow @yallascience

Donate

Contact Form

Name

Email *

Message *

Followers

29.12.11

anaphoresis



anaphoresis [PHYS CHEM] Upon application of an electric field, the movement of posi
tively charged colloidal particles or macromolecules suspended in a liquid toward
the anode

analytical extraction



analytical extraction [ANALY CHEM] Precise transfer of one or more components of a
mixture (liquid to liquid, gas to liquid, solid to liquid) by contacting the mixture
with a solvent in which the component of interest is preferentially soluble

analytical distillation


analytical distillation [ANALY CHEM] Precise resolution of a volatile liquid mixture into
its components; the mixture is vaporized by heat or vacuum, and the vaporized
components are recondensed into liquids at their respective boiling points

analog


analog [CHEM] A compound whose structure is similar to that of another compound
but whose composition differs by one element

anagyrine



anagyrine [ORG CHEM]C15H20N2O A toxic alkaloid found in several species of Lupinus
in the western United States; acute poisoning produces nervousness, depression,
loss of muscular control, convulsions, and coma

anabasine



anabasine [ORG CHEM] A colorless, liquid alkaloid extracted from the plants Anabasis
aphylla and Nicotiana glauca; boiling point is 105 C; soluble in alcohol and ether; used
as an insecticide

amyl xanthate



amyl xanthate [ORG CHEM] A salt formed by replacing the hydrogen attached to the
sulfur in amylxanthic acid by a metal; used as collector agent in the flotation of
certain minerals

amyl salicylate



amyl salicylate [ORG CHEM]C6H4OHCOOC5H11 A clear liquid that occasionally has a
yellow tinge; boils at 280 C; soluble in alcohol, insoluble in water; used in soap and
perfumes. Also known as isoamyl salicylate

amyl nitrite



amyl nitrite [ORG CHEM] (CH3)2CH(CH2)2NO2 A yellow liquid; soluble in alcohol, very
slightly soluble in water; fruity odor; it is flammable and the vapor is explosive; used
in medicine and perfumes. Also known as isoamyl nitrite

amyl ether



amyl ether [ORG CHEM] 1. Either of two isomeric compounds, n-amyl ether or isoamyl
ether; both may be represented by the formula (C5H11)2O. 2. A mixture mainly of
isoamyl ether and n-amyl ether formed in preparation of amyl alcohols from amyl
chloride; very slightly soluble in water; used mainly as a solvent

amylene



amylene [ORG CHEM]C5H10 A highly flammable liquid with a low boiling point, 37
38.5 C; often a component of petroleum. Also known as 2-methyl-2-butene

n amylamine



n-amylamine [ORG CHEM]C5H11NH2 A colorless liquid with a boiling point of 104.4 C
soluble in water, alcohol, and ether; used in dyestuffs, insecticides, synthetic deter-
gents, corrosion inhibitors, and pharmaceuticals, and as a gasoline additive

28.12.11

amyl alcohol


amyl alcohol [ORG CHEM]
 1. A colorless liquid that is a mixture of isomeric alcohols
2. An optically active liquid composed of isopentyl alcohol and active amyl alcohol

amyl acetate



amyl acetate [ORG CHEM]CH3COO(CH2)2CH(CH3)2 A colorless liquid, boiling at 142 C
soluble in alcohol and ether, slightly soluble in water; used in flavors and perfumes.
Also known as banana oil; isoamyl acetate

amyl



amyl [ORG CHEM] Any of the eight isomeric arrangements of the radical C5H11 or a
mixture of them. Also known as pentyl

amphoterism


amphoterism [CHEM] The property of being able to react either as an acid or a base

amphoteric



amphoteric [CHEM] Having both acidic and basic characteristics. Also known as
amphiprotic

27.12.11

ampholytic detergent


ampholytic detergent [CHEM] A detergent that is cationic in acidic solutions and
anionic in basic solutions

amphiphile



amphiphile [CHEM] A molecule which has a polar head attached to a long hydrophobic
tail

amphipathic molecule



amphipathicmolecule [ORG CHEM] A molecule having both hydrophilic and hydropho
bic groups; examples are wetting agents andmembrane lipids such as phosphoglycer-
ides

amperometry



amperometry [PHYS CHEM] Chemical analysis by techniques which involve measuring
electric currents

amperometric titration


amperometric titration [PHYS CHEM] A titration that involves measuring an electric
current or changes in current during the course of the titration

amount of substance



amount of substance [CHEM] A measure of the number of elementary entities present
in a substance or system; usually measured in moles

ammonolysis



ammonolysis [CHEM] 
1. A dissociation reaction of the ammonia molecule producing
H+ and NH2 species.

 2. Breaking of a bond by addition of ammonia. 

ammonium vanadate



ammonium vanadate [INORG CHEM]NH4VO3 A white to yellow, water-soluble, crystal
line powder; used in inks and as a paint drier and textile mordant

ammonium thiocyanate



ammonium thiocyanate [ORG CHEM]NH4SCN Colorless, deliquescent crystals with a
melting point of 149.6 C; soluble in water, acetone, alcohol, and ammonia; used in
analytical chemistry, freezing solutions, fabric dyeing, electroplating, photography,
and steel pickling

ammonium sulfide



ammonium sulfide [INORG CHEM] (NH4)2S Yellow crystals, stable only when dry and
below 0 C; decomposes on melting; soluble in water and alcohol; used in photo-
graphic developers and for coloring brasses and bronzes



ammonium sulfamate [INORG CHEM]NH4OSO2NH2 White crystals with a melting point
of 130 C; soluble in water; used for flameproofing textiles, in electroplating, and as
an herbicide to control woody plant species.

ammonium stearate


ammonium stearate [ORG CHEM]C17H35COONH4 A tan, waxlike substance with a melt
ing point of 73–75 C; used in cosmetics and for waterproofing cements, paper,
textiles, and other materials.

ammonium soap



ammonium soap [ORG CHEM] A product from reaction of a fatty acid with ammonium
hydroxide; used in toiletry preparations such as soaps and in emulsions

ammonium salt


ammonium salt [INORG CHEM] A product of a reaction between ammonia and various acids; examples are ammonium chloride and ammonium nitrate

14.12.11

ammonium persulfate


ammonium persulfate [INORG CHEM] (NH4)2S2O8 White crystals which decompose on
melting; soluble in water; used as an oxidizing agent and bleaching agent, and in
etching, electroplating, food preservation, and aniline dyes

ammonium perchlorate


ammonium perchlorate [INORG CHEM]NH4ClO4 A salt that forms colorless or white
rhombic and regular crystals, which are soluble in water; it decomposes at 150 C,
and the reaction is explosive at higher temperatures

ammonium iodide


ammonium iodide [INORG CHEM]NH4I A salt prepared from ammonia and hydrogen
iodide or iodine; it forms colorless, regular crystals which sublime when heated;
used in photography and for pharmaceutical preparations.

ammonium gluconate


ammonium gluconate [ORG CHEM]NH4C6H11O7 A white, crystalline powder made from
gluconic acid and ammonia; soluble in water; used as an emulsifier for cheese and
salad dressing and as a catalyst in textile printing

ammonium formate


ammonium formate [ORG CHEM] HCO2NH4 Deliquescent crystals or granules with a
melting point of 116 C; soluble in water and alcohol; used in analytical chemistry
to precipitate base metals from salts of the noble metals.

ammoniumfluoride


ammoniumfluoride [INORG CHEM]NH4F A white, unstable, crystalline salt with a strong
odor of ammonia; soluble in cold water; used in analytical chemistry, glass etching,
and wood preservation, and as a textile mordant

ammoniumdichromate


ammoniumdichromate [INORGCHEM] (NH4)2Cr2O7 A salt that forms orange,monoclinic
crystals; made from ammonium sulfate and sodium dichromate; soluble in water
and alcohol; ignites readily; used in photography, lithography, pyrotechnics, and
dyeing. Also known as ammonium bichromate

ammonium chromate


ammonium chromate [INORG CHEM] (NH4)2CrO4 A salt that forms yellow, monoclinic
crystals; made from ammonium hydroxide and ammonium dichromate; used in
photography as a sensitizer for gelatin coatings.

ammonium chloride


ammonium chloride [INORG CHEM]NH4Cl A white crystalline salt that occurs naturally
as a sublimation product of volcanic action or ismanufactured; used as an electrolyte
in dry cells, as a flux for soldering, tinning, and galvanizing, and as an expectorant.

ammonium carbonate


ammonium carbonate [INORG CHEM]
 1. (NH4)2CO3 The normal ammonium salt of carbonic acid, prepared by passing gaseous carbon dioxide into an aqueous solution
of ammonia and allowing the vapors (ammonia, carbon dioxide, water) to crystallize.

2. NH4HCO3 NH2COONH4 A white, crystalline double salt of ammonium bicarbonate
and ammonium carbamate obtained commercially; the principal ingredient of smell-
ing salts.

ammonium carbamate


ammonium carbamate [INORG CHEM] NH4NH2CO2 A salt that forms colorless, rhombic
crystals, which are very soluble in cold water; an important, unstable intermediate
in the manufacture of urea; found in commercial ammonium carbonate.

ammonium bromide


ammonium bromide [INORG CHEM]NH4Br An ammonium halide that crystallizes in
the cubic system; made by the reaction of ammonia with hydrobromic acid or
bromine; used in photography and for pharmaceutical preparations (sedatives).
{ ə mo ¯ n yəm bro ¯ mı ¯d}