An organic compound contains C, H, N, and O. Combustion of 0.1023 g of the compound in excess oxygen yielded 0.2766 g of CO2 and 0.0991 g of H2O. A sample of 0.4831 g of of the compound was analyzed for nitrogen by the Dumas method. At STP, 27.6 mL of dry N2 was obtained. In a third experiment the density of the compound as a gas was found to be 4.02 g/L at 127°C and 256 torr. What are the empirical formula and the molecular formula of the compound? (Type your answer using the format CO2 for CO2.)
2007-09-27 15:50:55 · 1 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
This is not a beginners question, so I assume you know about moles. Convert the gram quantities to moles in the ususal way. Use the ideal gas law to convert the volume of N2 to moles.
The yield of CO2 and H2O tells you precisely how much carbon and hydrogen are in the origianl compound (law of definitie proportions). 0.2766 g of CO2 (12/44) gives grams of C.
Once you everything in moles, calculate the EF. The last piece about the density goes back again to the ideal gas law. You can get moles and based on the grams, you can get the molecular mass. Combined with the EF, gives the true MF.
Good luck. Interesting problem
2007-09-27 15:59:21 · answer #1 · answered by reb1240 7 · 0⤊ 0⤋