Across
- 2. an ancient branch of natural philosophy, a philosophical and protoscientific tradition
- 3. a discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents.
- 5. the smallest unit of matter
- 8. chemical compound with the chemical formula CH4
- 10. a substance with a specific composition
- 11. pure chemical substance composed of more than one element
Down
- 1. said to have first made the atom theory
- 4. a unit of measurement that denotes an amount of substance
- 5. The rarest natural occurring element
- 6. process that leads to the chemical transformation of one set of chemical substances to another.
- 7. the scientific study of life and living organisms
- 9. small, dense region consisting of protons and neutrons at the center of an atom