To calculate the enthalpy change for the desorption of water vapor from the silica gel desiccant, we first need to determine the heat absorbed by the silica gel during the process. We can do this using the formula:q = mcTwhere q is the heat absorbed, m is the mass of the silica gel, c is the specific heat capacity of the silica gel, and T is the change in temperature.Given the information provided:m = 5.0 gc = 1.16 J/gCT = 40.0 C - 25.0 C = 15.0 CNow we can calculate the heat absorbed by the silica gel:q = 5.0 g 1.16 J/gC 15.0 C = 87.0 JSince the heat absorbed by the calorimeter is -222.4 J, and we are assuming that all the heat absorbed by the calorimeter comes solely from the desorption of water vapor, the enthalpy change for the desorption of water vapor is equal to the heat absorbed by the silica gel minus the heat absorbed by the calorimeter:H = q_silica_gel - q_calorimeter = 87.0 J - -222.4 J = 87.0 J + 222.4 J = 309.4 JTherefore, the enthalpy change for the desorption of water vapor from the silica gel desiccant is 309.4 J.