a white corrosive substance existing in three crystalline forms of which the stable (alpha-) form is usually obtained as silky needles. It is produced by the oxidation of sulphur dioxide, and is used in the sulphonation of organic compounds. Formula: SO 3: Systematic name: sulphur(VI) oxide
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How to use sulphur trioxide in a sentence
sulphur trioxide forms thin needle-shaped crystals, arranged in feathery groups.Poisons: Their Effects and Detection | Alexander Wynter Blyth
sulphur trioxide is a colorless liquid, which solidifies at about 15° and boils at 46°.
Small quantities of sulphur trioxide (SO3) may also be formed in the combustion of sulphur.
sulphur trioxide is formed, and as it issues from the tube it is absorbed in water or dilute sulphuric acid.
Such oxides as sulphur trioxide, nitrogen pentoxide, etc., do not possess acid properties except in combination with water.Heroes of Science | M. M. Pattison Muir