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 moles of H2: Molar mass of H2 = 2 * 1.008 g/mol = 2.016 g/mol Moles H2 = Given mass / Molar mass = 4.0 g / 2.016 g/mol = 1.984 mol H2 2. Use 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 H2O = 1.984 mol H2 * (2 mol H2O / 2 mol H2) = 1.984 mol H2O 3. Calculate grams of H2O: Molar mass of H2O = (2 1.008 g/mol) + (1 15.999 g/mol) = 18.015 g/mol Grams H2O = Moles H2O Molar mass H2O = 1.984 mol 18.015 g/mol = 35.744 g H2O 4. Round to appropriate significant figures: Since the given mass (4.0 g H2) has two significant figures, the answer should also be rounded to two significant figures. Grams H2O ≈ 36 g