When 3.2 g sulphur is vaporised at 450^(@)C and 723 mm Hg pressure, the vapours occupy a volume of 780 mL. What is the molecular formula of S vapours ?

When 3.2 g sulphur is vaporised at 450^(@)C and 723 mm Hg pressure, th

1.	When 3.2 g sulphur is vaporised at 450^(@)C and 723 mm Hg pressure, the vapours occupy a volume of 780 mL. What is the molecular formula of S vapours ?
Answer» `S_(2)` `S_(4)` `S_(6)` `S_(8)` Solution :(d) From ideal gas equation, `pV=(w)/(M)RT` `THEREFORE``M=(3.2xx0.0821xx760xx1000xx723)/(723xx780)=256` `because` 32 g of SULPHUR has 1 atom of S. `therefore` Molecular formula=`S_(8)`