10.1 Energy
1. Energy is the capacity to do work or to supply heat.
2. Chemical potential energy is energy stored in chemicals because of their compositions. Usually within the bonds of the molecules. Break bonds - release energy: decomposition. Build bonds - requires energy: synthesis.
3. Different substances store different amounts of energy. The kinds and arrangement of the atoms determines the amount of energy.
4. Heat, represented by q, is a form of energy that always flows from a warmer object to a cooler object. Adding heat changes temperature.
5. The law of conservation of energy states that in any chemical or physical process, energy is neither created nor destroyed. All of the energy involved a process can be accounted for as work, stored energy, or heat. In a process energy may be converted to an unusable form; however it is still accounted for.
6. Thermochemistry is the study of the heat changes that occur during chemical reactions and physical changes of state.
10.2 Heat Capacity
1. One calorie is the quantity of heat that raises the temperature of 1 g of pure water 1oC.
2. One dietary calorie "C" = 1 kcalorie.
3. One joule (SI unit of heat) of heat will raise the temperature of g of pure water .239oC.
4. CONVERSION UNITS: 1 kcal = 4186 J, 1 J = .239 cal, 1cal = 4.186 J.
5. Amount of heat to change an objets temperature by exactly 1oC is heat capacity.
6. Heat capacity of an object depends on mass and chemical composition.
7. Do problems 6 & 7.
10.3 Specific Heat Capacity
1. Specific heat (C) of a substance is amount of heat required to raise temp of 1 g of a substance 1oC.
2. Higher specific heat requires more heat to raise temp. Cools more slowly. Gives off more heat when cooling.
3. See Table 10.1
4. Heat (calorie or J) = mass x C x change temp.
5. C (Specific Heat)= q/m x dT = heat(J)/mass g x change temp.
6. Example 1, page 267
10.4 Exothermic and Endothermic Processes
1. See Lab C20.
2. A system is the specific part of the universe
on which you focus your attention. The surroundings include
everything outside the system. Together, the system and surroundings
constitiute the universe.
3. A process that absorbs heat from the surroundings
is called an endothermic process. (Surroundings
cool down)
4. A process that loses heat to the surroundings is called
an exothermic process. (Surrondings
heat up).
10.7 Heat and Changes of State
1. When ice melts the ice and water stay at 0oC until all the ice melts. Temerature of water goes up after all ice melts.
2. Molar heat of fusion is the heat
absorbed by one mole of a substance in melting from a solid to a liquid
at a constant temperature -
3. Molar heat of solidification is
the heat lost when one mole of a liquid changes to a solid at a constant
temperature. 
4. Energy is conserved: heat absorbed = heat lost.
5. Melting of 1 mol of ice at 0oC to 1 mol of water at 0oC requires absorption of 6.01 kJ of heat. Formation of 1 mol of ice at 0oC releases 16.01 kJ.
6. Example 4., problem 22.
7. Molar heat of vaporization is heat absorbed by a vaporization of a liquid (boiling or evaporation).
8. Table 10.6 gives some.
9. Molar heat of condensation is heat lost when vapor condenses to a liquid.
10. Heat lost by condensation of steam on skin causes skalding.
11. Example 5., problem 24.
12. Molar heat of solution is heat change when a substance is dissolved in a solvent. Can be exothermic or endothermic. Lab C21.
13. Example 6.
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