SULPHUR TRIOXIDE,

PHOSPHORUS TRIOXIDE,

Copper sulphide (Cus) contains 66.5 % Cu copper axide (CuO) contains 79.9% Cu and sulphur trioxide (SO_(3)) containts 40% S . Shows that these compounds obey the law of recipreocal proportions. Strategy: Elements S and O chemically combine seperately with element Cu to from Cus adn CuO . Elements S and O also chemicaly combine with each other to form SO_(3) . Find the ratio of masses of S to O combining with a given mass of Cu and also find the ratio of masses of S to O in SO_(3) .

Solid SeO_3 (selenium trioxide) and TeO_3 exist respectively as

Oxidation of sulphur dioxide into sulphur trioxide in the absence of a catalyst is a slow process but this oxidation occurs easily in the atmosphere. Explain how does this happen? Give chemical reactions for the conversion of SO_(2) into SO_(3) .

In trimer form of sulphurc trioxide, each sulphur atom s bonded with:

Write the balanced chemical equations for the following reactions : (i) "Hydrogen + Chlorine " to " Hydrogen chloride" (ii) "Magnesium oxide + Carbon " to " Magnesium + Carbon monoxide" (iii) "Phosphorus pentachloride + Water " to " Phosphoric acid + Hydrogen chloride" (iv) "Sulphur dioxide + Oxygen " to " Sulphur trioxide" (v) "Sodium + Water " to " Sodium hydroxide + Hydrogen" .