When 5.325 g KCL dissolves in 100.0ml of water the temperature decreases from 24.1 c to 21.2 c. Calculate the change in enthalpy per mole of KCL. Determine if the process is endothermic or exothermic.

You add some of the white crystals to a small test tube filled with water. The water in the test tube was initially at room temperature (25˚C). Once the crystals were added and the tube was stirred, the temperature of the solution decreased to about 15˚C and all of the crystals dissolved. what is the change in enthalpy (∆H) for this process?

A reaction between Mg and aqueous hydrochloric acid was performed to determine the heat of the reaction. A calorimeter with a heat capacity of 6.5 J/K was used. To the calorimeter 50.0 mL of 1.0 M HCI was added, the initial temperature was recorded and then 0.250 g of magnesium metal was added. The final temperature was then recorded. (Assume density of the solution is 1.03 g/mL; q = MCAT ; molar mass Mg = 24.31 g/mol; specific heat capacity of water = 4.184 J/g.K; q calorimeter = heat capacity x AT). The following data was recorded:Initial temperature:21.5°c ; Final Temperature: 45.1°c Calculate calorimeter (J) q solution (J) total amount of heat released (J), mol Mg, enthalpy of reaction in kJ/molor (q total/mol Mg). Just put the numerical values since units are already indicated. For the question, amount of heat released, there is no need to put the negative sign.

After a few minutes on the hot plate some sodium bicarbonate (NaHCO3) begins to decompose into sodium carbonate, CO₂(g) and H₂O(g). Using standard enthalpies of formation, calculate the enthalpy change for this reaction. Use the following data. The standard enthalpy of formation for NaHCO3 is -997 KJ/Mol and sodium carbonate is -468 KJ/Mol.