A student dissolves 13.8g of sodium chloride in of water in a well-insulated open cup. He then observes the temperature of the water fall from 20°C to 19.1° over the course of 5.1 minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction:
NaCl(s) → Na+ (aq) + Cl-(aq)

You can make any reasonable assumptions about the physical properties of the solution. Be sure answers you calculate using measured data are rounded to the correct number of significant digits. Note for advanced students: it's possible the student did not do the experiment carefully, and the values you calculate may not be the same as the known and published values for this reaction.

Is this reaction exothermic, endothermic or neither?
If you said the reaction was exothermoc or endothermic, calculate the amount of heat that was released or absorved by the reaction in this case.
Calculate the reaction enthalpy per mole.