Across
- 4. number of protons in nucleus
- 6. smallest indivisible part of an element
- 9. formed when a metal gives 1+ electrons to a non-metal so they both have full outer shells
- 10. more reactive halogens........ less reactive ones
- 12. giant ionic crystal
- 14. simple covalent substance (CH4)
- 19. group 7
- 21. formed when metals become cations in a sea of electrons
- 23. smallest mass and orbit the nucleus of an atom
- 24. 2+ atoms covalently bonded together
- 26. positive ion
- 28. group 0
- 29. columns in periodic table
Down
- 1. elements that exist as 2 atoms
- 2. burns red when in contact with air/oxygen
- 3. metals which form coloured compounds and complex ions
- 4. group 2
- 5. rows in periodic table
- 7. table with all atoms in it
- 8. these forces are weak between covalent molecules
- 11. 2+ atoms chemically joined together
- 13. formed when 2+ atoms share electrons
- 15. halogen ion
- 16. noble gases are very ........
- 17. poor conductor low melting point
- 18. giant covalent structure, hardest substance known to man
- 20. group 1
- 22. formed by gain or loss of electrons
- 24. good conductor, high melting point
- 25. made up of 1 type of atom only
- 27. total mass of protons and neutrons in an atom