Question

combustion analysis of a hydrocarbon produced: 33.01 g CO2 and 13.51 g H2O

Calculate the empirical formula of the Hydrocarbon.

I got CH5 but that doesn't seem right? how do i do this problem?

Answer 1

look at the mole ratios

CxHy >>> xCO2 + (y/2)H2O

well, on the right, you have how many moles of C?
answer: 33.01/(12+32)= ??? moles of CO2, and that is the same number of moles of C,
how many moles of H...ans: 13.51/(2+16), and moles of H is twice that (there are two moles of H in H2)

so take those two numbers, moles C, moles H, and divide EACH by the smaller.

You should get a whole number ration, such as 2:3, or 1:4, or such. Those numbers are the x,y in the CxHy

Answer 2

CH2