To determine the enthalpy change of the reaction when sodium chloride (NaCl) dissolves in water, we need to know the concentration of NaCl in the resulting solution. With the given information of 5.73 g of NaCl dissolved in 100 cm^3 (or 100 mL) of water, we can calculate the molarity (concentration) of the NaCl solution.
First, we need to convert the mass of NaCl to moles. The molar mass of NaCl is approximately 58.44 g/mol.
Mass of NaCl = 5.73 g Molar mass of NaCl = 58.44 g/mol
Number of moles of NaCl = Mass of NaCl / Molar mass of NaCl = 5.73 g / 58.44 g/mol
Now we can calculate the concentration (molarity) of NaCl in the solution:
Molarity (M) = Number of moles of solute / Volume of solution in liters
Volume of solution in liters = 100 cm^3 / 1000 cm^3/L = 0.1 L
Molarity of NaCl = Number of moles of NaCl / Volume of solution in liters = (5.73 g / 58.44 g/mol) / 0.1 L
Now, to determine the enthalpy change (ΔH) of the reaction, we would need the enthalpy of solution or dissolution of NaCl in water. This value represents the energy change associated with the process of dissolving NaCl in water and is typically provided as experimental data or tabulated values.
Without the specific enthalpy of solution for NaCl, it is not possible to calculate the enthalpy change of the reaction based solely on the given information. The enthalpy change would depend on the specific conditions and temperature at which the dissolution occurs.