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Heat Of Formation Of Nacl Essay

1151 Words5 Pages

Kim B. Dy 7F
Experiment #5 Heat of Formation of NaCl(s) October 28, 2015

ABSTRACT In Heat of Formation of NaCl(s), two chemical reactions in the form of the neutralization between NaOH(aq) and HCl(aq) and the dissolution of NaCl(s) to NaCl(aq) were performed. Calorimetry and the First Law of Thermodynamics were employed to find out the respective enthalpies of the reactions. These two values completed the Table of Thermochemical Equations given and with respect to Hess’s Law, the heat of formation of solid NaCl was computed by adding the enthalpies in the table. Two Styrofoam cups and a thermometer through its lid served as the calorimeter where the reactions took place. Using the heat transfer equation, the enthalpy of the first reaction was computed to be
-1.080 kJ/mol. On the other hand, the enthalpy of the second reaction was +1.409 kJ/mol. The first reaction had a negative enthalpy and was therefore an exothermic reaction. The positive enthalpy of the second reaction showed that it was endothermic. Given the completed Table of Thermochemical Equations, the total of enthalpies was computed to be -355.521 kJ/mol.

INTRODUCTION …show more content…

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