How do you determine the empirical formula of a compound that has the following composition: 92.3 percent C and 7.7 percent H?

1 Answer
Nov 7, 2016

Answer:

As with all these problems, we assume that there are #100*g# of unknown compound........to give an empirical formula of #CH#.

Explanation:

And then we work out the molar composition.

Thus #"Moles of carbon"# #=# #(92.3*g)/(12.011*g*mol^-1)=7.68*mol#.

And #"Moles of hydrogen"# #=# #(7.7*g)/(1.00794*g*mol^-1)=7.64*mol#.

Clearly, there is #1:1# molar equivalence with respect to #C:H#.

The molecular formula is a multiple of the empirical formula, but we have no handle on that here.