An organic compound contains carbon, hydrogen and nitrogen. A 2.000 gram sample of this compound is burned in a combustion analysis chamber. The drying tube collects 1.555 grams of water. The sodium hydroxide tube collects 5.429 grams of carbon dioxide. (a) Explain what is the weight of nitrogen contained in this 2.000 gram sample? (b) Explain if the molar mass is found to be in the range of 120~200 g/mol, define what is the molecular formula of the compound?