When 2.137 g of A_x (s) dissolves in 148.3 g of water in a coffee-cup calorimeter, the temperature rises from 23.7 , ° C to 35.2 , ° C. Calculate the enthalpy change (in kJmol) for the solution process.
a) 15.72
b) 31.44
c) 62.88
d) 125.76