Chemistry and more!

1234567891011
Across
  1. 2. an ancient branch of natural philosophy, a philosophical and protoscientific tradition
  2. 3. a discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents.
  3. 5. the smallest unit of matter
  4. 8. chemical compound with the chemical formula CH4
  5. 10. a substance with a specific composition
  6. 11. pure chemical substance composed of more than one element
Down
  1. 1. said to have first made the atom theory
  2. 4. a unit of measurement that denotes an amount of substance
  3. 5. The rarest natural occurring element
  4. 6. process that leads to the chemical transformation of one set of chemical substances to another.
  5. 7. the scientific study of life and living organisms
  6. 9. small, dense region consisting of protons and neutrons at the center of an atom