| A | B |
|---|
| Chemical potential energy | solar energy in a different form saved in fossil fuels |
| Bituminous Coal | softer coal used to produce thermal energy |
| Anthracite Coal | hardest coal |
| Fossil Fuel | the remains of ancient plants and animals |
| Natural Gas | Fossil Fuel that was created from plants and animals under ancient seas. |
| Oil | less dense than water, but more dense than natural gas. |
| Permeable rock | holes in rock are connected so oil and water can flow through. |
| Porous rock | has holes in it but the holes are not connected. Oil and water can not flow through it. |
| Sandstone | porous and permeable rock that that allows oil and water to flow through. |
| Shale | porous but not permeable rock that will not allow water and oil to flow through |
