1. Energy
16.1

3. The Nature of Energy Energy is the ability to do work or produce heat.
Two types of energy: kinetic and potential
Example: skier
Potential energy of a substance depends on its composition: the type of atoms in the substance, the number and type of chemical bonds joining the atoms, and the particular way the atoms are arranged.

4. The Nature of Energy Continued
Law of Conservation of Energy (first law of thermodynamics)
The law of conservation of energy states that in any chemical reaction or physical process, energy can be converted into one form or another but it’s neither created nor destroyed.
Chemical potential energy
Chemical potential energy is the energy that is stored in a substance because of its composition.
Example: Gasoline
Heat
Heat (q) which is energy that is in the process of flowing from a warmer object to a cooler object.

5. Measuring Heat
calorie (cal) is the amount of energy required to raise the temperature of one gram of pure water by 1oC.
One Nutritional Calorie (Cal) equals 1000 calories (cal) or 1 kilocalorie
The SI unit of energy and of heat is joule (J)
One calorie (cal) = joules (J)

6. Specific Heat 4.184 J/goC is specific heat of water (c)
The specific heat of any substance is the amount of heat required to raise the temperature of one gram of that substance by 1o Celsius.
Calculating heat absorbed
q = mc∆T
q = heat absorbed or released (J)
m = mass of sample (g)
c = specific heat of substance J/g oC
∆T = change in temp in oC (Tfinal – Tinitial)

7. Specific Heat Chart Substance J/goC Aluminum 0.900 Bismuth 0.123
Copper
0.386
Brass
0.380
Gold
0.126
Lead
0.128
Iron
0.449
Silver
0.233
Tungsten
0.134
Zinc
0.387
Mercury
0.140
Alcohol (ethyl)
2.44
Water (liquid)
4.184
Ice (-10)
2.03
Water (gas)
2.01
Granite
0.790
Concrete/Glass
0.840