What is the enthalpy change (ΔH) for the reaction when 200.0 mL of 0.100 M AgNO3 is mixed with 100.0 mL of 0.100 M NaCl in a coffee cup calorimeter, given that the temperature rises from 24.69°C to 25.16°C and the calorimeter has a heat capacity of 105.5 J/°C?

• A. -3.56 kJ/mol
• B. -2.47 kJ/mol
• C. -1.23 kJ/mol
• D. -0.98 kJ/mol

Answer: (B)

Verified step by step guidance

1. Calculate the total volume of the solution by adding the volumes of AgNO3 and NaCl solutions: 200.0 mL + 100.0 mL.
2. Determine the total heat absorbed by the solution using the formula q = C_calorimeter * ΔT, where C_calorimeter is the heat capacity of the calorimeter and ΔT is the change in temperature.
3. Calculate the change in temperature (ΔT) by subtracting the initial temperature from the final temperature: 25.16°C - 24.69°C.
4. Use the formula ΔH = -q to find the enthalpy change for the reaction, where q is the heat absorbed by the solution.
5. Convert the enthalpy change from joules to kilojoules and then to kJ/mol by considering the moles of the limiting reactant, which can be calculated from the molarity and volume of the solutions.