Across
- 2. orbits the nucleus in particular energy levels
- 3. substance containing multiple elements
- 10. graphic arranging all elements in a logical order
- 11. number written below each elemental symbol on the periodic table
- 13. positively charged subatomic particle
- 14. a variant of an element with a different atomic mass
- 15. rows in the periodic table
- 16. the fundamental unit of all matter
Down
- 1. equal to the number of protons
- 4. substance containing multiple compounds
- 5. energy level that negatively charged particles orbit in
- 6. cluster of subatomic particles in the centre of an atom
- 7. uncharged particle residing in the nucleus of an atom
- 8. columns in the period table
- 9. equal to the total number of protons and neutrons
- 12. different type of atoms