OSMIUM (IV) OXIDE Property

Density 

11.4

solubility 

insoluble in H2O, acid solutions

form 

Powder

Specific Gravity

11.4

color 

Black

Water Solubility 

Slightly soluble in cold water.

Crystal Structure

Rutile type

crystal system

square

Space group

P42/mnm

Lattice constant

a/nm	b/nm	c/nm	α/o	β/o	γ/o	V/nm3
0.4503	0.4503	0.3184	90	90	90	0.0646

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

OSMIUM (IV) OXIDE Chemical Properties,Usage,Production

Chemical Properties

Osmium (IV) oxide is a dark bluish black powder(s), with rutile crystal(s) form [KIR82] [ALD94]. Insoluble in water and acids. Forms OsO4 on heating in air; readily reduced to the metal by H2.

Uses

The osmium oxide/hexacyanoruthenate films modified electrodes plays an important role for the electrocatalytic reaction of catecholamines and sulfur oxoanions. Used as catalyst. Metallic osmium or an osmium oxide-ruthenium cyanide film modified graphite electrodes plays an essential role for the determination of biogenic amines from electrocatalytic responses.

Preparation

Osmium (VIII) oxide is reduced in the cold by a stream of H2. If, however, the OsO4 is heated in the H2 stream, the product is the metal. Osmium (IV) oxide can also be prepared by heating a fine powder consisting of a mixture of K2OsCl3 and three times its amount of Na2C03. The temperature should be lower than red heat; the cooled product is extracted with water which is slightly acidified with dilute hydrochloric acid. The product is perfectly pure OsO2.

Safety Profile

Brown or black crystals. Amorphous form can explode spontaneously in air. When heated to decomposition it emits toxic fumes of Os.

Structure and conformation

Crystal structure of Osmium (IV) oxide: rutile type.