Measure out approximately 3 g of hydrated copper(II) sulfate on one of the four-place balances, then use a mortar and pestle to pulverize it as fine as you can get it. Dissolve in approximately 25 mL of distilled water which you have previously massed out on the same balance. Carefully measure the temperature change with the thermister connected to the ULI.

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Pour your solution into a pre-massed Petri dish labeled with your initials and set aside to allow the water to evaporate.

Obtain another 3 gram sample and place the sample in a previously massed evaporating dish. Do not pulverize this sample. Heat on a hot plate on medium heat for about ten minutes. Cool and mass. Reheat for another minute, cool again and remass. If the mass is within 0.03 grams you can consider all of the water of hydration to be removed. If not, continue until you have reached this amount.

Repeat the first part of this lab with your heated sample. DON'T forget to get the mass of the water you put in the coffee cup calorimeter.

Calculate the value of "q" for the water in the calorimeter and then ΔH of solution in kJ/mol for both the hydrated and anhydrous samples.

Calculate the coefficient of the waters of hydration for the hydrated copper(II) sulfate.

Write the balanced equation for the dissolving of the two different samples, the hydrated and anhydrous samples and calculate the theoretical values of ΔH of solution for each. Then calculate your percent error.

Use the values of ΔH_f from your reference tables to do the calculations of theoretical values.