Across
- 1. substance elements or compounds
- 3. what happens when two substances interact
- 4. a thing that is composed of two or more separate elements
- 6. two substances combined
- 7. each of more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter
- 10. an atom with a negative charge
- 12. Gases elements on the periodic table that we're long believed to be unreactive to anything
- 15. absorbs heat
- 18. Table the most common way to organise learn the elements
- 19. Democritus’ version of the atom
Down
- 1. Atom with a positive charge
- 2. the most reactive nonmetal elements on the periodic table
- 5. physical substance in general (what everything is made of)
- 6. a group of atoms bonded together
- 8. releases heat
- 9. Metals the most reactive elements on the periodic table
- 11. the basic unit of a chemical element.
- 13. not a nonmetal, but not a metal
- 14. characteristics of a substance
- 16. Mass how many atoms are in an element
- 17. a compound or substance that has been purified or prepared, especially artificially