What is Osmium Tetroxide?

Osmium tetroxide is an inorganic molecule containing one Osmium atom and four oxygen atoms. Osmium tetroxide is identified in several different ways, these ways include OsO4 and Osmium(VIII) oxide. The central atom of Osmium tetroxide is Osmium (Os) which is a very rare element that was discovered by accident in 1803. Osmium tetroxide has many uses considering the rarity of Osmium. Osmium tetroxide has a molecular structure that resembles a tetrahedron with 109.5 degree bond angles. All four Osmium - Oxygen bonds in OsO4 are double bonds, consisting of two shared electrons from Osmium being contributed to each Oxygen atom. Osmium tetroxide is a very volatile molecule, and is highly toxic and corrosive. Due to this, it must be properly stored in glass container.

Osmium tetroxide is normally a yellowish color, although in its purest form it is thought to be clear. The yellowish tinge is usually attributed to the possible presence of OsO2. Osmium tetroxide has an odd, acrid odor which is described as the smell of o-zone. The Greek root Osme in Osmium actually means odor. This molecule is usually found in the form of a pale yellow solid. However, OsO4 sublimes at room temperature. Osmium tetroxide has a melting point of 40.25 degrees Celsius and a boiling point of 129.7 degrees Celsius. It also has a density of 4.91g/cm³ and a molar mass of 254.23 grams/mole.

Polarity of OsO4

As shown in this picture, the Oxygen atoms have a slightly more negative charge. This is because Oxygen atoms have an electronegativity of 3.5 while Osmium is only 2.2. Due to the tetrahedron structure of Osmium tetroxide, this molecule is nonpolar because no side is slightly more negative than any other.

Due to the nonpolarity of Osmium tetroxide, the only forces acting upon it between other molecules are London dispersion forces.

London dispersion forces are there temporary attraction between nonpolar molecules when the constantly moving electrons cause the molecules to become instantaneously polar. When this occurs, a temporary dipole is formed which can attract other temporary dipoles.

Why Not Purchase Some Osmium Tetroxide?

Osmium tetroxide has many practical uses in chemistry, but due to its volatile nature it should be handled with care. Osmium tetroxide is used in many chemical processes such as organic synthesis, biological staining, polymer staining, Osmeth, and Osmium ore refining. One major quality about Osmium tetroxide is that it is soluble in most organic solvents and is moderately soluble in water. With so many uses why wouldn't you buy some? For the modest price of just over $300/gram!

Avoid ingestion, eye contact, and skin contact. Proper safety procedures are necessary for safe use. Prices are according to set prices on sciencelab.com

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The Many Uses of Osmium Tetroxide

• Osmium tetroxide is used in organic synthesis to oxidize alkenes.
• Osmium tetroxide is used in biological staining as a staining agent for transmission electron microscopy to provide contrast. It is also used as a lipid stain in scanning electron microscopy.
• In polymer staining, Osmium tetroxide is used to stain copolymers.
• To store Osmium tetroxide without it emitting toxic fumes, Osmium tetroxide can be complexed with hexamine to form Osmeth. Osmeth is a golden colored solid that is not volatile unlike Osmium tetroxide. A working solution can be made from the Osmeth through diluting the substance.
• Osmium tetroxide can be refined through several chemical processes to form pure Osmium.

WARNING

• Due to the high toxicity of Osmium tetroxide, it should be handled with care.
• Even at very low exposure levels it can be very dangerous.
• Inhalation of Osmium tetroxide can cause pulmonary edema, possibly resulting in death.
• Symptoms can take hours to appear after exposure.
• Osmium tetroxide can stain the human cornea and cause blindness.
• Osmium tetroxide should be stored in glass containers because it can penetrate plastics.