Calorimetry 2: Hot and Cold Reactions Overview Getting Started Techniques Procedure FAQ Full Lab Manual Introduction & Goals Chemistry & Background Key Questions Prelab Problems Safety Procedure In Your Write-up Experiments Index ChemLab Home		FAQ Index Question 1 How do I figure out how much salt to use? Question 2 How can I be sure to transfer all the salt into the calorimeter? Why can't I rinse the beaker or weighing paper with water? Submissions Submit a question or an answer to the FAQ Questions & Answers Question 1 How do I figure out how much salt to use? Professor Milde First, calculate the heat required to increase the temperature of the calorimeter by the desired amount. Then figure out how much salt would be required to produce or absorb this amount of heat. You will need to calculate the heat of solution for your chosen salts in kJ per mole and kJ per gram. Question 2 How can I be sure to transfer all the salt into the calorimeter? Why can't I rinse the beaker or weighing paper with water? Professor Milde You will have to work out the best way to transfer the salt to the calorimeter. If you rinse the beaker with additional water, you will change the heat capacity of the calorimeter and some of the heat of solution will be absorbed or released outside the calorimeter. Also, the masses of solt you calculate to give approximately a 3 degree Celsius temperature change are relatively large and hard, if not impossible, to mass on a piece of weighing paper. Keep this in mind when you work out the details of your procedure. Submissions Submit to the FAQ You can submit either a question or an answer to a question about this week's experiment. Your submission will be mailed to the site editor, who will respond to you directly and also add your submission to the FAQ page. Having trouble with the submission procedure? Check your Kerberos installation. If you lose the FAQ Submission window it may be hidden behind another browser window.
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