When 0811 G of NH₄NO₃ Was Added to 150

Multiple Choice

When 0.811 g of NH₄NO₃ was added to 150.0 g of water in a Styrofoam cup,the temperature dropped by 0.413°C.The heat capacity of H₂O is 4.18 J/g°C.Assume the specific heat of the solution equals that of pure H₂O and that the calorimeter neither absorbs nor leaks heat.The molar heat of solution of solid NH₄NO₃ is:

A) +257 J/mol
B) +25.7 kJ/mol
C) +2.57 kJ/mol
D) -2.57 kJ/mol
E) -257 J/mol