| A | B |
|---|
| geothermal | when the Earth's heat is the energy source |
| nuclear | the type of energy stored in the nuclei of atoms |
| fission | a reaction where the nucleus of an atom is split |
| fusion | a reaction where the nuclei of atoms are bonded together |
| chemical | fuel cells store this type of energy |
| hydroelectric | moving water used as a type of energy source |
| biomass | animal dung and plant matter used as fuel |
| fossil fuels | materials we burn for energy that originated as plants and animals |
| solar | type of energy from the nuclear fusion of the sun |
| wind | air currents used as a type of energy source |
| gasohol | a combination of gasoline and grain alcohol |
| coal | solid fossil fuel |
| natural gas | gaseous fossil fuel |
| petroleum | liquid fossil fuel |
| natural resource | something the Earth makes and we use |
| renewable resource | something we use that can be regenerated in our life time |
| nonrenewable resource | something we use that cannot be regenerated in our life time |
| smog | a combination of fog and smoke |
| acid precipitation | happens when water vapor combines with chemicals in the air |
| reduce | to use less |
| reuse | to use for a different purpose |
| recycle | to break down and reuse the raw materials |
