101 G CaO Is Dropped into a Styrofoam Coffee Cup $\circ$

Multiple Choice

10.1 g CaO is dropped into a styrofoam coffee cup containing 157 g H₂O at 18.0 ^$\circ$ C.If the following reaction occurs, what temperature will the water reach, assuming that the cup is a perfect insulator and that the cup absorbs only a negligible amount of heat (The specific heat of water = 4.18 J/g· ^$\circ$ C)
CaO(s) + H₂O(l) $\rarr$ Ca(OH) ₂(s) $\Delta$ H ^$\circ$ _rxn = -64.8 kJ/mol

A) 18.02 ^$\circ$ C
B) 35.8 ^$\circ$ C
C) 42.2 ^$\circ$ C
D) 117 ^$\circ$ C
E) 311 ^$\circ$ C