Across
- 4. smallest building block of matter
- 7. positively charged component of atom
- 9. substance made by only one kind of atom
- 10. two or more atoms joined together
- 12. electrons in the outer shell
- 14. substance composed of two or more kinds of atoms chemically joined
- 17. number of protons
- 18. atoms that gain electrons
- 19. different number of protons and electrons
Down
- 1. vertical column of periodic table
- 2. elements that conduct heat and electricity
- 3. neutral charged component of atom
- 5. element has different number of neutrons
- 6. negatively charged component of atom
- 8. horizontal column of periodic table
- 11. energy level that electrons are in
- 13. elements that do not conduct heat or electricity
- 15. atoms that lose electrons
- 16. number of protons and neutrons combined