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
Welcome back veale — missed you this week. Let's find the molecular formula of the hydrocarbon. Step 1: Determine the empirical formula from the percentage composition. Assume 100 g of the compound. Mass of Carbon (C) = 80 g Mass of Hydrogen (H) = 20 g Moles of Carbon = Mass / Molar mass = 80 g / 12 g/mol = 6.67 mol Moles of Hydrogen = Mass / Molar mass = 20 g / 1 g/mol = 20 mol Divide by the smallest number of moles to find the simplest ratio: For C: 6.67 / 6.67 = 1 For H: 20 / 6.67 ≈ 3 The empirical formula is CH₃. Step 2: Determine the molar mass of the compound. Given that 1 dm³ of the gas at S.T.P. weighs 1.35 g, and 1 mole of gas at S.T.P. occupies 22.4 dm³. Molar mass = (Mass of 1 dm³) × (Molar volume at S.T.P.) Molar mass = 1.35 g/dm³ × 22.4 dm³/mol Molar mass = 30.24 g/mol Step 3: Determine the molecular formula. First, calculate the empirical formula mass for CH₃: Empirical formula mass = (1 × Atomic mass of C) + (3 × Atomic mass of H) Empirical formula mass = (1 × 12 g/mol) + (3 × 1 g/mol) = 12 + 3 = 15 g/mol Now, find the factor 'n' by which the empirical formula must be multiplied: n = Molar mass / Empirical formula mass n = 30.24 g/mol / 15 g/mol n ≈ 2.016 ≈ 2 (round to the nearest whole number) Finally, multiply the empirical formula by 'n' to get the molecular formula: Molecular formula = (CH₃)₂ = C₂H₆ The molecular formula of the hydrocarbon is C₂H₆. Send me the next one 📸