A 6.89 g sample of an unknown salt (MM = 116.82 g/mol) is dissolved in 150.00 g water in a coffee cup calorimeter. Before placing the sample in the water, the temperature of the salt and water is 23.72 C. After the salt has completely dissolved, the temperature of the solution is 28.54 C. What quantity in moles of the unknown salt were used in the reaction?