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 g of water are produced. Steps: 1. Calculate the moles of H2: Molar mass of H2 = 2 * 1.008 g/mol = 2.016 g/mol Moles of H2 = Mass / Molar mass = 4.0 g / 2.016 g/mol = 1.984 mol H2 2. 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. Moles of H2O = 1.984 mol H2 * (2 mol H2O / 2 mol H2) = 1.984 mol H2O 3. Calculate the mass of H2O: Molar mass of H2O = (2 1.008 g/mol) + (1 15.999 g/mol) = 18.015 g/mol Mass of H2O = Moles Molar mass = 1.984 mol 18.015 g/mol = 35.74 g H2O Rounding to two significant figures (due to 4.0 g H2), the mass of water produced is 36 g.