One gram of an element was found to contain 0.835 gram of chlorine its vapour density is 85. Find the molecular formula of chloride.

Wt. of element = 1-0.835 = 0.165 gmeq. wt of element =0.1650.835×35.5=7.014Let x be the valency of elementAt. wt of element = 7.014 xthe molecular formula of chloride MClxM.wt of chloride = 7.014x + x.35.3=V.D. × 2(42.314)x = 2 × 85∴ x = 4Hence molecular formula = MCl4