Thonum oxide

Thorium oxide has a high refractive index and low dispersion and thus finds use in high-quality camera and scientific instrument lenses. Thonum oxide also is used as a catalyst in the conversion of ammonia to nitnc acid, in petroleum cracking, and in sulfuric acid production. 

Thorium occurs in monazite sand in Brazil, India, North and South Carolina this ore contains 3-9% thorium oxide, and is the chief source thorium is also found in thorite containing about 60% oxide and in thorianite. about 80% oxide. When heated with concentrated H2SO4 the minerals form thonum sulfate, from which, by a senes of reactions, thonum nitrate, the chief commercial compound, is obtained. 

Light frequently exerts a considerable influence on the rate of oxidation 1 thus phosphorus trichloride when illuminated undergoes more rapid conversion into the oxychloride 2 than in the dark and iron likewise corrodes more rapidly m similar circumstances. Oxidation may be catalytically accelerated by radio-active substances. Thus thonum-X has been found 3 to assist the oxidation of adrenaline and morphine. 

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