periodic table
Across
- 3. the mass of an atom of chemical element
- 5. a solid material that is typically hard
- 12. something that stands for or represents something else
- 14. subatomic particle with a zero charge
- 15. an element or substance that is not a metal
- 16. elements that form a salt when it reacts to metal
- 17. a simple way of writing down the locations of all of the electrons
- 18. horizontal lines on the periodic table
- 21. subatomic particle with a negative charge
Down
- 1. an element whose properties are in between metals and non-metals
- 2. basic unit of a chemical element
- 4. elements that form
- 6. subatomic particle with a positive charge
- 7. clear model of an atom
- 8. compounds
- 9. the number of protons in the nucleus
- 10. electrons in the outer shell of an atom
- 11. elements used to make steel and iron
- 13. a table of chemical elements
- 19. a part or aspect of something abstract
- 20. vertical columns on the periodic table