[The_Journey]

I'm not asking for answers, I'm asking on what steps should I be using to solve this (apparently) really tough question.

An unknown compound contains Carbon, Hydrogren, and Nitrogen. Upon analysis it is found to contain 60% Carbon. When 4.00-g of the compound is burned, all of the hydrogen is converted to 0.033-moles of water.

a) What is the weight of each element in a 4.00-g sample of the unknown compound?

b) What is the empirical formula?

For a, I converted 0.033-moles of water to 0.594g of water and then found the mass of the Hydrogen, which is 0.066g.
60% of Carbon in a 4.00-g sample means there is 2.4g of Carbon in the sample.
Then for Nitrogen, I subtracted 0.066g and 2.4g from 4.00g to get 1.534g as the mass for Nitrogen

I'm stuck at b, I converted Hydrogen, Carbon, and Nitrogen into moles, which turned out to be 0.2 mol of C, 0.11 mol of N, 0.066 mol of H. Then I tried dividing them all to find the whole number ratios, that is when I got ridiculous numbers for the unknown compound. I think I got like C9H3N5 as the formula for the unknown compound, which is obviously wrong.

Can someone help me to find what I did wrong?

Thank you.

[opti384]

I took a glance at your process and it seems fine. I'm not sure what C9H3N5 is, but organic compounds' formulas could look bizarre or C9H3N5 could just be contrived for the problem.

[Borek]

http://www.chemdrug.com/databases/10_2_bmspwiiwhsprwywe.html