0.2g of an organic compound on analysis give 0.147g of carbondioxide, 0.12 g of water and 74.6 c,c of nitrogen at S.T.P. Calculate the weight percentages of constituents.

Explanation

Weight of compound = w = 0.2 h , volume of `N_(2)` at STP = `v_(2)` = 74.6 cc
`%C = (w_(1)xx12xx100)/(wxx44) = (0.147xx12xx100)/(0.2xx44) = 20.04%`
`%H = (w_(2)xx2xx100)/(wxx18) = (0.12xx2xx100)/(0.2xx18) = 6.66%`
`%N = (v_(2)xx25 xx100)/(wxx22400) = (0.74.6)/(8xx0.2) = 46.63%`
Weight percentage of oxygen is obtained indirectly
`%O = 100 = (%C+%H+%N) = 100-73.33 = 26.67%`