Heat Capacity of Metals A. Calorimetry = science of measuring heat changes (uses a calorimeter) Each substance changes temperature at a different rate = Heat Capacity Specific Heat capacity = J/g•oC = Cs = Sh Molar Heat capacity = J/mol•oC Water has a high heat capacity Very good coolant Heat change = q = Sh x m x DT 2. Constant-Pressure Calorimeter Experiment done under atmospheric pressure 44.0 g hot iron (100 oC) is added to 100 g of cool water (20.0 oC) in a calorimeter T = 23.6 oC after the temperature stabilizes (equilibrium) Key Concept: all of the heat lost from the iron goes to the water qwater = qiron

Procedure Use water bath on a hot plate to heat metal in a test tube, record Temp Record the initial temperature and weight of your calorimeter (calorimeter = two styrofoam cups) Add the hot metal to the calorimeter and record the final (highest) Temp Weigh the calorimeter + metal Repeat two more times to get an average specific heat of the metal Repeat the whole thing on a second metal Recycle the cups and the metal: don’t throw them away Deviation from the mean = |Shi – Shavg|

Incident: Broken Mercury Thermometer