Dictionary, Defintion, Meaning, What is Arrhenius Equation, Ascorbic Acid, Vitamin, Arsenate, Arsenic, Arsenic (III) oxide Arsenic Trioxide, Arsenious Oxide, white Arsenic

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Dictionary of Chemistry Dictionary of Chemistry - Part 1 Part 2 ASS Atomic Absorption Spectroscopy - ABS Plastics Accumulator - Acetophenone Acetyl Coenzyme A - Acid base Indicator Acidic Dissociation Constant - Actinium Compounds Activated Molecule - Acyloin Condensation Adenosine Monophosphate - Aerosol,Aerogel Albumin (Albumen) - Aldosterone Alkaline Earth Metals - Alkanes (Paraffins) Alkynes (Acetylenes) - Allotropy(Allotrope) Aluminates - Aluminium Alkoxides Aluminium Silicates - Alums Amine Oxides - Amino Acids Aminoplastie Resins - Ammonium Carbonate Ammonium Phosphates - Amphoteric Amyl ether - Andrews Titration Angstrom - Anode Mud Anti isomorphism - Antimonyl Derivatives Apatite - Arndt Eistert Synthesis Arrhenius Equation - Ascorbic Acid, Vitamin Asphaltic Bitumen - Atactic Polymers

Home >> Chemistry Dictionary >>Arrhenius Equation - Ascorbic Acid, Vitamin

Your Ad Here	Arosolan process A process for the extraction of benzene. Arrhenius equation. The variation in the rate of a chemical reaction with temperature can be complied quantitatively by the Arthenius equation. k = A exp(-E_a / RT) where k is the velocity constant, A and Ea are constante termed the pre-exponential factor and the activation energy, of the particular reaction being considered (R is the gas constant). The pre-exponential factor A is a collision frequency factor, which is comparatively insensitive to temperature. A = pZ where Z is the collision frequency and p is a ‘steric factor’, which is the measure of the efficiency of the collision for effective reaction. The Arrhenius equation applies to process such as diffusion, electrolytic conduction, viscous flow, etc., and as well as chemical reactions.
Arsenate. A metal of arsenic acid H₃ASO₄ Arsenic. Symbol As. A metalloid element of group V of the periodic table; a.n. 33; r.a.m. 74.92; r.d. 5.7; sublimes at 613°C. It has three allotropes-yellow, black, and grey. They grey metallic form is the stable and most common one. Arsenic compounds are used in insecticides and as doping agents in semiconductors. The element is included in some lead-based alloys to promote hardening
Arsenic (III) oxide (arsenic trioxide; arsenious oxide; white arsenic). A white or colourless compound.: AS4O₆, existing in three solid forms. The commonest has cubic or octahedral crystals (r.d. 3.85 ; sublimes at 193°C) and is soluble in water, ethanol, and alkali solutions. It occurs naturally as arsenolite. A vitreous form can be prepared by slow condensation of the vapour (r.d. 3.74); its solubility in cold water is more than double that of the cubic form. The third modification, which occurs naturally as claudetite, has monoclinic crystals (r.d. 4.15). Arsenic (III) oxide is obtained commercially as a byproduct from the smelting of nonferrous sulphide ores; it may be produced in the laboratory by burning elemental arsenic in air.	Your Ad Here
The structure of the molecule is similar to that of P₄O₆, with a tetrahedral arrangement of As atoms edge linked by oxygen bridges. Arsenic (III) oxide is acidic; its solutions were formerly called arsenious acid (technically, arsenic (III) acid). It arsenate (III) salts (formerly called arsenites). Arsenic (III) oxide is extremely toxic and is used as a poison for vermin; trace doses are used for a variety of medicinal purposes. It is also used for producing opalescent glasses and enamels.
Your Ad Here	Arsine (AsH₃). A colourless gas with a garlic odour. It is insoluble in water. It is usually prepared in the laboratory by the action of metal and dilute acid on arsenious oxide e.g., Zn + HCl ----> ZnCI₂ + 2(H) (nascent) As₂O₃ + 2(H) ----> 2ASH3 ¯ + 3H₂O It burns in air with a bluish white flame forming water and arsenious oxide. 2AsH₃ + 3O₂ ----> 2As₂H₃ ¯ + 3 H₂O It is used in the detection of arsenic. Artinite. A mineral form of basic magnesium carbonate MgCO₃ Mg(OH)₂3H₂O.

Aryl.
When a hydrogen atom is removed from a hydrocarbon of the benzene series, the residue is called an aryl group.

As.
Arsenic.

Asbestine.
A fibrous variety of tale mixed with termolite asbestos. Used as a rubber filler and in paints

Asbestos.
The fibrous varieties of a number of silicate minerals containing SiO₄ groups linked into chains. The most important are the fibrous amphiboles (tremlities crocidolites) and fibrous talcs and clay minerals (chrysotile). The fibres can be spun and woven into textile and used in fabrics for heart and electrical insulation and fire-proof fabrics. Used as a binder in asbestos-cement building materials and in fitration. Inhalation of certain asbestos fibres can cause asbestosis, a lung disease which is frequently fatal.

Ascarite.
Asbestos which in impregnated with molten NaOH. Used to absorb CO₂.

Ascorbic acid, vitamin.
C, C₆H₈O₆. m.p. 190-192°C. The enolic form of 3-oxo-L-gulofuranol-actone. It can be prepared by synthesis from glucose, or can be extracted from plant sources such as rose hips, blackcurrents or citrus fruits.
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Easily oxidized. It is essential for the formation of collagen and intercellular material, bone and teeth heating the wounds. It is used in the treatment of scurvy. Man is one of the few mammals unable to manufacture ascorbic acid in his liver. Used as a photographic developing agent in alkaline solution.

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Dictionary of Chemistry - Part 3 Part 4 Atomic Radius - Aufbau Principle Auger Effect - Azeotropic Mixtures Azimuthal Quantum Number - Babbit Metal Band Spectrum - Barometer Base Catalysed Reation - Backmann Thermometer Beneficiation (Ore Dressing) - Benzamide Benzidine Conversion - Benzoin Beryllate - Beta decay Bio Geneic Amines - Birkland Eyde Process Bitumen Emulsions - Blue Print Paper Bomb Calorimeter - Bordeaux Mixture Born Haber Cycle - Bornyl and Isobornyl Chlorides Boron Hydrides - Bredt's Rule Bromobenzens - Brown Ring Test Buchner Funel - Butanedioic Acid Cadmium Chemistry - Calcination Calcium Chloride - Calcium Phosphates Calorimeter - Carbanion Carbon Dating - Carbon Residue Carmine - Castner Kellner Cell

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