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CHEM 1011. Calorimetry: The Determination of the Specific Heat of a Metal. Calorimetry. Calorimetry – the science of measuring heat transfer. Calorimetry. Principle of Conservation of Energy-
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CHEM 1011 Calorimetry: The Determination of the Specific Heat of a Metal
Calorimetry • Calorimetry – the science of measuring heat transfer.
Calorimetry • Principle of Conservation of Energy- Energy can neither be created nor destroyed in any process, but can be transferred from one part of a system to another
Calorimetry • Calorimeter – device used to measure heat – calorimeter cup and thermometer.
Calorimetry • Specific heat – the amount of heat needed to raise temperature of 1 g of a substance 1° C. • Specific heat is an intensive property.
Calorimetry • Specific heat values are generally lower for metals and higher for non-metals (see Table 9.1).
Calorimetry • When a given mass of a substance undergoes a temperature change, the equation showing the relationship between quantity of heat, specific heat, mass, and temperature change is Q = SH x m x ΔT ΔT = Tfinal - Tinitial
Calorimetry • Heat lost by one substance is equal to the heat gained by the other. Qlost = Qgained
Heat Capacity of the Calorimeter • Because calorimeter absorbs heat, must calculate Ccal.
Heat Capacity of the Calorimeter • Construct graph and extrapolate maximum temperature.
Heat Capacity of the Calorimeter ΔT of cold water and calorimeter = (5) – (3)
Heat Capacity of the Calorimeter ΔT of warm water = (5) – (4)
Heat Capacity of the Calorimeter Heat lost by warm water = (2) x 1.00cal/gºC x (7)
Heat Capacity of the Calorimeter Heat gained by cold water & calorimeter = - (8)
Heat Capacity of the Calorimeter Heat gained by cold water = (1) x 1.00cal/gºC x (6)
Heat Capacity of the Calorimeter Heat gained by the calorimeter = (9) – (10)
Heat Capacity of the Calorimeter Heat capacity of calorimeter, Ccal = (11) / (6)
Specific Heat of a Metal Mass of metal = (3) – (2)
Specific Heat of a Metal • Construct graph and extrapolate maximum temperature.
Specific Heat of a Metal ΔT of cold water and calorimeter = (7) – (5)
Specific Heat of a Metal Heat gained by calorimeter and water = [(1) x 1.00cal/gºC x (8)] + [Ccal x (8)]
Specific Heat of a Metal ΔT of the metal = (7) – (6)
Specific Heat of a Metal Heat lost by the metal = - (9)
Specific Heat of a Metal Specific heat of the metal = (11) / [(4) x (10)]
Specific Heat of a Metal • According to the Law of Dulong and Petit, SHmetal x gram atomic mass = 6.3 cal/moleºC • Rearranged, it becomes gram atomic mass = 6.3 cal/moleºC / SHmetal
Specific Heat of a Metal Atomic mass = 6.3 cal/moleºC / (12)