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 — missed you this week. Here's the solution to question 23: Given: Mass of hydrated sodium carbonate (Na_2CO_3 · XH_2O) = 2.86 g Mass of anhydrous sodium carbonate (Na_2CO_3) = 1.06 g Atomic masses: Na = 23.0 g/mol, C = 12.0 g/mol, O = 16.0 g/mol, H = 1.0 g/mol. Step 1: Calculate the molar mass of anhydrous sodium carbonate (Na_2CO_3). Molar mass of Na_2CO_3 = (2 × 23.0) + 12.0 + (3 × 16.0) = 46.0 + 12.0 + 48.0 = 106.0 g/mol a) The number of moles of anhydrous sodium carbonate in the residue. Moles of Na_2CO_3 = Mass of Na_2CO_3Molar mass of Na_2CO_3 = 1.06 g106.0 g/mol = 0.0100 mol The number of moles of anhydrous sodium carbonate is 0.0100 mol. b) The number of moles of water of crystallization present in the hydrated carbonate. First, calculate the mass of water lost: Mass of H_2O = Mass of hydrated salt - Mass of anhydrous salt Mass of H_2O = 2.86 g - 1.06 g = 1.80 g Next, calculate the molar mass of water (H_2O): Molar mass of H_2O = (2 × 1.0) + 16.0 = 2.0 + 16.0 = 18.0 g/mol Now, calculate the number of moles of water: Moles of H_2O = Mass of H_2OMolar mass of H_2O = 1.80 g18.0 g/mol = 0.100 mol The number of moles of water of crystallization is 0.100 mol. c) Deduce the formula of the hydrated sodium carbonate. To find the value of X in Na_2CO_3 · XH_2O, we need the mole ratio of H_2O to Na_2CO_3. Ratio X = Moles of H_2OMoles of Na_2CO_3 = 0.100 mol0.0100 mol = 10 The formula of the hydrated sodium carbonate is Na_2CO_3 · 10H_2O. Send me the next one 📸