0.2046g of an organic compound gave 30.4ml of moist nitrogen measured at 288K and 732.7mm pressure. Calculate the percentage of nitrogen in the substance

Question

Chemistry questions 

Answer 1

In order, you need to look up the vapor pressure of water at 288K, subtract it from 732.7mm. This gives the partial pressure of the N2 component of the measured gas sample. You now have enough data to solve pV=nRT for n; substitute in the MW of N2 gas to get the mass of N so contained. Ratio that to the original weight of compound, express as percentage. P.S.: Can you provide some possible formulas for the original compound -- you may want to compare to a few simple molecules -- BUT, bear in mind that much better tools exist in the lab for this task, such as mass spectrometry, even IR spectroscopy.