Stannic oxide

Chemical properties

white or off-white powder

Physical properties

White or grayish powder; tetragonal crystals; density 6.85 g/cm³; refractive index 2.006; Mohs hardness 6.5; melts at 1,630°C; insoluble in water; soluble in hot concentrated alkalies.

The Uses of Stannic oxide

Stannic oxide (SnO2) is a whitish powder used as a ceramic glaze and polishing agent.

The Uses of Stannic oxide

Polishing glass and metals; manufacture of milk-colored, ruby and alabaster glass, enamels, pottery, putty; mordant in printing and dyeing fabrics; in fingernail polishes.

The Uses of Stannic oxide

It is used to detect carbon monoxide. Used in ceramic glazes and colors, putty, perfume preparations, textiles, polishing powder for steel, and the manufacture of special glasses. Stannic oxide is also used in making white patinas.

Preparation

Tin(II) oxide is prepared by heating tin(II) hydroxide. The latter is obtained as a white precipitate by reacting Sn²+ ions with hydroxide ions: Sn₂+(aq) + 2OHˉ(aq) → Sn(OH)₂ (s) Sn(OH)₂ ?→ ?? SnO(s) + H₂O(g).

Definition

ChEBI: Tin dioxide is a tin oxide compound consisting of tin(IV) covalently bound to two oxygen atoms.

General Description

White or off-white crystalline solid or powder. Mp 1127°C, Sublimes: 1800-1900°C, density: 6.95 g cm-3. Insoluble in water. Soluble in concentrated sulfuric acid, hydrochloric acid. Occurs in nature as the mineral cassiterite. Used as a catalyst, in putty, as a polishing powder for steel and glass, in ceramic glazes and colors. Flowers of tin refers to the material collected as the result of condensation after sublimation.

Reactivity Profile

TIN(IV) OXIDE is non-flammable and non-combustible. Reacts vigorously with strong reducing agents. Incompatible with chlorine trifluoride.

Purification Methods

Reflux it repeatedly with fresh HCl until the acid shows no tinge of yellow. The oxide is then dried at 110o.