Across
- 1. atomic mass minus atomic number
- 4. the numbers in chemical formulas
- 6. different versions of the same element
- 8. its chemical symbol is O
- 10. negative charge orbits the nucleus
- 12. neutral charge, found in the nucleus
- 14. positive charge, in the nucleus
- 15. the building blocks of matter
- 16. matches the number of protons in an atom
Down
- 2. center of the atom, home to protons and neutrons
- 3. anything that has mass and takes up space
- 5. the atomic number tells us the amount of these
- 7. a pure substance made from one type of atom
- 9. compounds are expressed using symbols and numbers
- 11. made from 2 or more elements
- 13. each element has a unique one of these