Final answer:
The student's question involves thermochemistry and the calculation of enthalpy change (ΔH) for an exothermic reaction where potassium reacts with water to release energy. Using the details provided about the mass, temperature change, and specific heat, the enthalpy change per mole can be calculated.
Step-by-step explanation:
The question presented involves the concept of thermochemistry, which is the study of heat energy associated with chemical reactions. In the example provided, 60.0 g of potassium metal reacts with water to release hydrogen gas and form potassium hydroxide with an associated energy release of 160 kJ. This type of reaction is called an exothermic reaction because it releases heat to the surroundings.
To calculate the enthalpy change (ΔH) of a reaction per mole, we can use the information given for the specific heat and mass of potassium hydroxide dissolved.
By knowing the mass of the substance, the volume of the solvent, the initial and final temperatures, and the specific heat of the solution (assumed equal to that of pure water), we can determine the ΔHsoln (enthalpy change of solution).
For instance, in a separate example provided, when 5.03 g of solid potassium hydroxide are dissolved in water, the temperature increase allows us to calculate that 5.13 kJ of energy is released in the process. Then, by using the molar mass of KOH, we can find out the enthalpy change for one mole of KOH.