1. Aim: How to measure molar heat of solution DO NOW: Get into groups of 3 or 4 and compare your homework. You have 5 minutes.

2. Try it out! A student performed an experiment in which she dissolved a salt in water. She took the initial temperature of the water, before dissolution of the salt, to be 23 o C. After the salt was completely dissolved in the water the temperature of the solution dropped to 19 o C. Was the dissolution of the salt and exothermic or endothermic process? Explain.

3. Calorimetry Calorimetry is the measurement of heat flow into or out of a system for chemical or physical processes. In calorimetry, the heat released by a system is equal to the heat absorbed by its surroundings. Conversely, the heat absorbed by the system is equal to the heat released by the surrounding. http://highered.mheducation.com/sites/9834092339/ student_view0/chapter48/bomb_calorimeter.html http://highered.mheducation.com/sites/9834092339/ student_view0/chapter48/bomb_calorimeter.html

5. Heat of Solution Heat of Solution The Heat of Solution is the amount of heat energy absorbed (endothermic) or released (exothermic) when a specific amount of solute dissolves in a solvent. Molar heat of solution is the amount of energy absorbed or released per one mole of the solute.

6. Problem 1 In an experiment, a student added 1.01 grams of lithium bromide, LiBr, to 12.21 grams of water at 20.1°C. After stirring for awhile, the temperature of the mixture rose to 31.3°C. Given this information, we can calculate the molar heat of solution for lithium bromide.

7. Problem 2 A calorimeter was used to determine the molar enthalpy of a solution of AlCl 3. When a sample of AlCl 3 was dissolved in water the following data were collected. Determine the molar heat (kJ/mol) of solution. Mass of AlCl 3 (g) Mass of H 2 O (g) Initial Temp. ( o C) Final Temp. ( o C) 10.0250.020.046.3