0.5 gram of an organic compound contains 0.062 g of hydrogen and 0.25 g of oxygen. In the vapour state this compound weighs 32 times as heavy as the same volume of hydrogen. Determine the molecular formula.
Answers
Answer:
Therefore the formula of the organic compound is C2H8O2
Explanation:
The organic compound consists of carbon, hydrogen and oxygen.
0.5 gm of compound contains 0.062 gm of H and 0.25 gm of O
since Vapour density = 32
Since molar mass≈ 2*vapour density
Therefore, Molecular weight= 2 * 32 = 64
% of H in the organic compound = (0.062/0.5) * 100 = 12.4%
% of O in the organic compound = (0.25/0.5) * 100 = 50%
Therefore, % of C = 100- % of H - % of O
= 100- (12.4 + 50)
=37.6%
Therefore, moles of C= 37.6/12 = 3.13
moles of H = 12.4/1 = 12.4
moles of O = 50/16 = 3.13
Ratio of moles of C = 3.13/3.13= 1
Ratio of moles of H = 12.4/3.13 = 4
Ratio of moles of O = 3.13/ 3.13= 1
Therefore. the ration of C : H : O = 1: 4: 1
Empirical mass of the compound is 12 + 4 + 16 = 32
Empirical number n = 64/32 = 2