A pure sample contains 2.1 grams of nitrogen and 1.2 grams of oxygen. What is the empirical formula for the sample? Determine the empirical formula for each of the compounds described below. a. butanoic acid, C_4H_8O_2\b. acetylsalicylic acid, C_9H_8O_4\c. ethylenediamine, C_2H_8N...