Alumina oxide

• CAS No:

1344-28-1

• Formula:

Al2O3

• Chemical Name:

Alumina

Description

Vary according to the method of prepa- ration. White powder, balls, or lumps of various mesh.Insoluble in water, dif- ficultly soluble in mineral acids and strong alkali. Noncombustible.

Aluminum oxide is a white odorless crystalline powder. Water insoluble. Properties (both physical and chemical) vary according to the method of preparation; different methods give different crystalline modifications. The variety formed at very high temperature is quite inert chemically.|WHITE POWDER.|White, odorless, crystalline powder.

Aluminum oxide is a white odorless crystalline powder. Water insoluble. Properties (both physical and chemical) vary according to the method of preparation; different methods give different crystalline modifications. The variety formed at very high temperature is quite inert chemically.|Aluminum oxide has a chemical formula Al2O3. It is amphoteric in nature, and is used in various chemical, industrial and commercial applications. It is considered an indirect additive used in food contact substances by the FDA.|An oxide of aluminum, occurring in nature as various minerals such as bauxite, corundum, etc. It is used as an adsorbent, desiccating agent, and catalyst, and in the manufacture of dental cements and refractories.

Alumina oxide Basic Attributes

Molecular Weight ：101.96

Exact Mass ：101.947823

EC Number ：254-434-2

UNII ：LMI26O6933

ICSC Number ：0351

DSSTox ID ：DTXSID1052791

Color/Form ：White crystalline powder|White powder, balls or lumps or various mesh

ATC Code ：D – Dermatologicals

Characteristics

PSA ：3

XLogP3 ：0.31860

Appearance ：DERBY BROWN

Density ：4.0 g/cm³ @ Temp: 20 °C

Melting Point ：2000 °C (approx)

Boiling Point ：2980 °C

Flash Point ：2980°C

Refractive Index ：1.765

Water Solubility ：Miscible with ethanol.INsoluble

Storage Conditions ：Keep container tightly closed in a dry and well-ventilated place. strongly hygroscopic.

Vapor Pressure ：17 mm Hg ( 20 °C)

Toxicity ：Non-toxic

Flammability characteristics ：Noncombustible solid, but dusts may form explosive mixtures in air.

Odor ：Odorless

Experimental Properties ：Very hygroscopic; an electrical insulator, electrical resistivity at 300 °C about 1.2x10+13 ohms-cm; very hard, about 8.8 on Mohs' scale; when heated above 800 °C, becomes insoluble in acid; specific gravity increases from 2.8 to 4.0 when heated above 800 °C|White powder, hexagonal; MP: 2054 °C; BP: 2977 °C; density: 3.99 g/cu cm; insoluble in water, organic solvents; slightly soluble in alkaline solutions /Alpha-alumina/|Heat of formation: -130.0 kJ/mol; Gibbs energy of formation: -159.0 kJ/mol; molar entropy: 259.4 J/mol-K; molar heat capacity at constant pressure: 45.7 J/mol-K at 298.15 K|Enthalpy of fusion: 111.1 kJ/mol /Alpha-alumina/|Density: 3.97 g/cu cm; Mohs' hardness: 9; index of refraction: 1.761 (alpha), 1.769 (beta) /Corundum/|Ridgeway's hardness scale: 12; Knoop hardness: 21 kN/sq m|Mean specific heat: 795.5 J/kg-K from 25-1,800 °C; thermal conductivity: 10.9 W/m-K at 500 °C, 6.2 W/m-K at 1000 °C; linear thermal expansion coefficient: 8.6/deg C X 10+6, from 20-1000 °C

Air and Water Reactions ：Insoluble in water.

Reactive Group ：Non-Redox-Active Inorganic Compounds

Reactivity Alerts ：Known Catalytic Activity

Reactivity Profile ：ALUMINUM OXIDE is chemically amphoteric (behaves as a weak acid in the presence of base and as a weak base in the presence of acid). May act catalytically. May cause the exothermic polymerization of ethylene oxide. May cause the vigorous polymerization of vinyl chloride [MCA SD-75, 1970]. The degree of subdivision of the aluminum oxide may affect the vigor of such reactions.

Flammable Limits ：Noncombustible solid, but dusts may form explosive mixtures in air.

Alumina oxide Use

Aluminium oxide is a chemical compound of aluminium and oxygen with the chemical formula Al2O3. It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium(III) oxide. It is commonly called alumina, and may also be called aloxide, aloxite, or alundum depending on particular forms or applications. It occurs naturally in its crystalline polymorphic phase α-Al2O3 as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire. Al2O3 is significant in its use to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point.