Specific Heat Capacity and Latent Heat Unit 5: Heat

Specific Heat Capacity (c) The quantity of heat required to raise the temperature of a unit of mass by a unit change in temperature

example When 4.0 kg of water is cooled from 40oC to 5oC. How much heat energy is lost?

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assignment Specific heat practice problems Lab: specific heat capacity in liquids

Specific Latent Heat Is the quantity of heat energy required to change the state of a unit of mass of substance

Specific latent heat of fusion The quantity of heat energy released when 1 kg of substance solidifies without changing temperature Ex. how much heat energy is needed to change 2.0 kg of ice @ 0oC to water @ 0oC (lfus= 3.3x103 J/kg)

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Specific latent heat of vaporization- is the quantity of heat energy needed to vaporize 1 kg of substance without changing its temperature Ex. how much heat energy is needed to change 0.50 kg of water @ 100oc to steam @ 100oc? (lvap= 2.3x106 J/kg)

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Latent Heat applications Picnic coolers- ice in a cooler will absorb some heat from food keeping it @ a cool temperature Preventing frost damage-gardeners turn sprinklers on crops, because when the water hits the plants and starts to freeze it will actually release some heat to plant Cooling off when wet- when you get out of a shower the water will use your body heat to vaporize (if you don’t dry off) and since heat has left your body, you will feel cooler

Do practice problems Assignment- latent heat problems