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<li>When a student mixes 50 mL of 1.0 M HCl and 50 mL of 1.0 M NaOH in a coffee-cup calorimeter, the temperature of the resultant solution increases from 21.0 °C to 27.5 °C. Calculate the enthalpy change for the reaction in kJ per mol of HCl, assuming that the calorimeter loses only a negligible quantity of heat. The total volume of the solution is 100 mL, its density is 1.0 g/mL, and its specific heat is 4.18 J/g-K.
A. 2.7 kJ/mol
B. −2.7 kJ/mol
C. 54.4 kJ/mol
D. −54.4. kJ/mol
E. −108 kJ/mol</li>
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