This chemistry question involves key chemical concepts and calculations. The detailed solution below walks through each step, from identifying the reaction type to computing the final answer.
ScanSolve AI Answer
When 4.0 g of H2 reacts with excess O2, 36 grams of water are produced. Here are the steps: 1. Calculate the molar mass of H2 and H2O: Molar mass of H2 = 2 1.008 g/mol = 2.016 g/mol Molar mass of H2O = (2 1.008 g/mol) + 16.00 g/mol = 18.016 g/mol 2. Convert the given mass of H2 to moles: Moles of H2 = Mass of H2 / Molar mass of H2 Moles of H2 = 4.0 g / 2.016 g/mol = 1.984 mol H2 3. Use the mole ratio from the balanced equation to find moles of H2O: The balanced equation is 2H2 + O2 -> 2H2O. From the equation, 2 moles of H2 produce 2 moles of H2O. This is a 1:1 mole ratio. Moles of H2O = Moles of H2 = 1.984 mol H2O 4. Convert moles of H2O to grams: Mass of H2O = Moles of H2O Molar mass of H2O Mass of H2O = 1.984 mol 18.016 g/mol = 35.746 g 5. Round to appropriate significant figures: The given mass (4.0 g) has two significant figures, so the answer should also be rounded to two significant figures. Mass of H2O = 36 g