How do you find the elemental composition of carbon, hydrogen, and oxygen, of acetic acid?

1 Answer
Jun 24, 2017

Answer:

We divide the mass of carbon by the mass of the molecule, and multiply by #100%#.........

Explanation:

For #H_3C-CH_2OH#:

#"% carbon"=(2xx12.011*g*mol^-1)/(46.07*g*mol^-1)xx100%=52.1%#

#"% hydrogen"=(6xx1.00794*g*mol^-1)/(46.07*g*mol^-1)xx100%=13.1%#

#"% oxygen"=(1xx15.999*g*mol^-1)/(46.07*g*mol^-1)xx100%=34.7%#

Now #%C# and #%H# COULD be measured......(an analyst generally would not touch a liquid!). Oxygen content is a harder proposition, and generally when perform microanalysis on an organic sample we report #%C#, #%H#, and #%N#, the balance, i.e. the missing percentage that makes the sum of the other percentages #100%# is assumed to be due to oxygen.