| A | B |
|---|
| solar cell | converts sunlight directly into energy |
| reservoir | underground oil or natural gas accumulation |
| fossil fuel | coal |
| generator | converts kinetic energy to electrical energy |
| steam | spins turbine of coal-burning plant |
| compound | pure substance that can be broken down chemically |
| element | pure substance that cannot be changed into any other pure substance by ordinary means |
| atom | smallest particle of an element (potassium) |
| Dalton | person who said that elements are made of compounds |
| molecule | smallest particle of a compound (water) |
| density | the relationship of mass and volume of a material |
| prevailing westerlies | winds between 30 degrees and 60 degrees latiatude |
| radiation | heat transfered from the sun |
| conduction | process by which air gains heat throug contact with hot surfaces |
| convection | transfer of heat by movement of air mass |
| atmosphere | layers of gases around the earth |
