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
Step 1: Analyze the change in the number of moles of gas for each reaction. A decrease in entropy ( S < 0) typically occurs when the number of moles of gas decreases. A. N_2O_4(g) 2NO_2(g) Reactant moles of gas = 1 Product moles of gas = 2 Change in moles of gas ( n_gas) = 2 - 1 = +1. Entropy increases. B. N_2(g) + 3H_2(g) 2NH_3(g) Reactant moles of gas = 1 + 3 = 4 Product moles of gas = 2 Change in moles of gas ( n_gas) = 2 - 4 = -2. Entropy decreases. C. CaCO_3(s) CaO_(s) + CO_2(g) Reactant moles of gas = 0 Product moles of gas = 1 Change in moles of gas ( n_gas) = 1 - 0 = +1. Entropy increases. D. 2N_2H_4(l) + N_2O_4(l) 3N_2(g) + 4H_2O_(l) Reactant moles of gas = 0 (both are liquids) Product moles of gas = 3 Change in moles of gas ( n_gas) = 3 - 0 = +3. Entropy increases. The reaction accompanied by a decrease in entropy is B. The final answer is B Step 1: Calculate the molar mass of anhydrous copper (II) oxosulphate (VI), which is CuSO_4. Given atomic masses: Cu = 64, S = 32, O = 16. Molar mass of CuSO_4 = Cu + S + (4 × O) Molar mass of CuSO_4 = 64 + 32 + (4 × 16) Molar mass of CuSO_4 = 64 + 32 + 64 = 160 g/mol Step 2: Calculate the number of moles of CuSO_4. Given mass of CuSO_4 = 32 g. Moles of CuSO_4 = MassMolar mass Moles of CuSO_4 = 32 g160 g/mol = 0.2 mol Step 3: Calculate the heat of solution. Heat generated = 13.0 kJ. Heat of solution = Heat generatedMoles of solute Heat of solution = 13.0 kJ0.2 mol = 65.0 kJ/mol Since heat was generated, the process is exothermic, and the enthalpy change would be -65.0 kJ/mol. However, the options provide the magnitude. The final answer is B. 65.0 KJmol^-1 Send me the next one 📸