Calculating Heat Specific Heat l l Amount of

  • Slides: 11
Download presentation
Calculating Heat

Calculating Heat

Specific Heat l l Amount of heat energy needed to raise the temp of

Specific Heat l l Amount of heat energy needed to raise the temp of 1 ml of a substance 1°C For water the specific heat is 4. 19 J/g °C, but it is differenct for different substances It takes 4. 19 J to raise the temp of 1 g of water 1 °C Every substance has a different specific heat

Table of Specific Heats

Table of Specific Heats

Calculating Heat When Substance in One Phase l l Heat released or absorbed can

Calculating Heat When Substance in One Phase l l Heat released or absorbed can be calculated by multiplying three factors Heat = specific heat x mass x temp change q = c x m x Δt

Practice l l The specific heat of water is 4. 19 J/ g C.

Practice l l The specific heat of water is 4. 19 J/ g C. How much heat is needed to warm 350 g of water from 25 C to 75 C? If 178 J of heat is needed to increase the temperature of a 20 g piece of copper metal from 25 C to 48 C, what is the specific heat of copper?

Heat and Phase Change (Evaporation) l l l Heat of vaporization ( Hvao) energy

Heat and Phase Change (Evaporation) l l l Heat of vaporization ( Hvao) energy required to change one gram of a substance from liquid to gas. For water 2260 J/g Q = Hvao m

Practice l l The heat of vaporization of water is 2260 J/g. How much

Practice l l The heat of vaporization of water is 2260 J/g. How much heat must be supplied to evaporate 50 g of water? How much heat is required to evaporate 150. g of a substance at its boiling point if it has a Hvap= 987 J/g?

Energy and Phase Change l l l Heat of fusion ( Hfus) energy required

Energy and Phase Change l l l Heat of fusion ( Hfus) energy required to change one gram of a substance from solid to liquid. For water 340 J/g Q = Hfus m

Examples l l The heat of fusion of ice at 0°C is 340 J/g.

Examples l l The heat of fusion of ice at 0°C is 340 J/g. How much heat is needed to change 75 g of ice at 0°C to a liquid at the same temperature? The heat of fusion of water at 0°C is 340 J/g. How much heat is released when 250 g of water changes to ice at 0°C?

Practice l l How much heat is needed to change 100 g of water

Practice l l How much heat is needed to change 100 g of water at 50 C to steam at 120 C? The specific heat of water is 4. 19 J/g C, the specific heat of steam is 1. 7 J/g C, and the heat of vaporization of water is 2260 J/g. How much heat must be released as 50 g of water at 25 C to ice at -10 C? The specific heat of water is 4. 19 J/g C, the specific heat of ice is 2. 1 J/g C, and the heat of fusion fro water is 340 J/g.

Calculating specific heat capacities Calculating the specific heatCalculating specific heat capacities Calculating the specific heat
Calculating specific heat capacities Calculating the specific heatCalculating specific heat capacities Calculating the specific heat
Specific Heat HEAT SPECIFIC HEAT Specific heat PHASESpecific Heat HEAT SPECIFIC HEAT Specific heat PHASE
SPECIFIC HEAT Calculations SPECIFIC HEAT CAPACITY The amountSPECIFIC HEAT Calculations SPECIFIC HEAT CAPACITY The amount
Thermochemistry Specific Heat Specific Heat n Amount ofThermochemistry Specific Heat Specific Heat n Amount of
Thermal Energy Transfer Specific Heat Specific Heat AmountThermal Energy Transfer Specific Heat Specific Heat Amount
Specific Heat 1 Specific Heat is the amountSpecific Heat 1 Specific Heat is the amount
Specific Heat Part 1 Specific Heat Capacity SpecificSpecific Heat Part 1 Specific Heat Capacity Specific
SPECIFIC HEAT CAPACITY Heat SPECIFIC HEAT CAPACITY CSPECIFIC HEAT CAPACITY Heat SPECIFIC HEAT CAPACITY C
14 Heat Specific heat and Latent heat Heat14 Heat Specific heat and Latent heat Heat