Answer the following question: Ethanol, C2H5OH, is considered clean fuel because it burns in oxygen to produce carbon dioxide and water with few trace pollutants. If 325.0 g of H2O are produced during the combustion of ethanol, how many grams of ethanol were present at the beginning of the reaction? When answering this question include the following: Have both the unbalanced and balanced chemical equations. Explain how to find the molar mass of the compounds. Explain how the balanced chemical equation is used to find the ratio of moles (hint: step 3 in the video). Explain how many significant figures your answer needs to have. The numerical answer
127.88 grams of ethanol were present at the beginning of the reaction Explanation: Firstly, let's make the combustion reaction: C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O By 1 mol of ethanol, you can make 3 mole of water. Mole of water = Water mass / Molar mass 150g / 18g/m = 8.3 mole 3 mole of water came from 1 mol of ethanol 8.3 mole came from (8.3 .1)/3 = 2.78 mole of ethanol Molar mass ethanol = 46 g/m Mole . molar mass = mass 2.78 m . 46g/m = 127.88 g
