How do we find percentage composition of a compound, with respect to an element....?

1 Answer
Oct 17, 2016

#%# #"element"# #=# #"Mass of element"/"Mass of compound"xx100%.#

Explanation:

We don't know to what mass or to what compound you refer. So you should revise the question.

And so, were we asked to find elemental composition of methane...we would take the quotients...

#%C=(12.01*g*mol^-1)/(16.01*g*mol^-1)xx100%=75.0%#

#%H=(4xx1.00794*g*mol^-1)/(16.01*g*mol^-1)xx100%=25.0%#

And clearly, in a binary compound #%# calculation of one element, specifies percentage of the other element.