1. Ionic substances C2.1/2 10-Jul-11

6. Metal + Non-metal Metal atoms Non-metal atoms + ions– ions electrons Ionic compound Atoms get full outer shells by transfer of electrons.

7. xx xx x x x x x x x Na atom 2,8,1                Cl atom 2,8,7

8. xx xx x x x x x x x Na + ion [2,8] +                Cl atom 2,8,7 +

9. x Na + ion [2,8] +                Cl atom 2,8,7 xx xx x x x x x x +

10. x                Na + ion [2,8] + xx xx x x x x x x +

11. x                Cl – ion [2,8,8] - – Na atoms : Cl atoms react Na : Cl = 1 : 1 Na ions : Cl ions Na + : Cl – = 1 : 1 NaCl Na + ion [2,8] + xx xx x x x x x x +

12. Ions in the lattice are in the ratio: Na + : Cl - = 1 : 1 Formula = NaCl

13. xx xx x x x x x x x x Ca atom 2,8,8,2                Cl atom 2,8,7                xx xx x x x x

14. x x                               xx xx x x x x x x Ca 2+ ion [2,8,8] 2+ xx xx x x x x 2+

15. xx xx x x x x x x x x                Cl atom 2,8,7                2+ Ca 2+ ion [2,8,8] 2+

16. x x                Cl – ion [2,8,8] -                – – Ca atoms : Cl atoms react Ca : Cl = 1 : 2 Ca ions : Cl ions Ca 2+ : Cl – = 1 : 2 CaCl 2 xx xx x x x x x x 2+ Ca 2+ ion [2,8,8] 2+

17. Ca atoms : Cl atoms react Ca : Cl = 1 : 2 Ca ions : Cl ions Ca 2+ : Cl – = 1 : 2 CaCl 2

18. xx xx x x x x x x x x Mg atom 2,8,2         O atom 2,6

19. xx xx x x x x x x x x Mg 2+ ion [2,8,2] 2+         O atom 2,6 2+

20. xx xx x x x x x x x x Mg 2+ ion [2,8,2] 2+         O atom 2,6 2+

21. xx xx x x x x x x x x Mg 2+ ion [2,8,2] 2+         O 2- ion [2,8] 2- 2+2- Mg atoms : O atoms react Mg : O = 1 : 1 Mg ions : O ions Mg 2+ : O 2- = 1 : 1 MgO

22. Mg atoms : O atoms react Mg : O = 1 : 1 Mg ions : O ions Mg 2+ : O 2- = 1 : 1 MgO

23. True or False? 1.Each molecule of sodium chloride contains one sodium ion and one chloride ion. 2.Each sodium ion is attracted to one chloride ion, and each chloride ion to one sodium ion. 3.The ionic bond is the donation of one electron from each sodium atom to each chlorine atom. 4.The fomula NaCl means that one sodium ion is bonded to one chloride ion. FALSE

24. True or False? 5.Sodium chloride has a high melting point because there is a strong attractive force between ions of opposite charge. 6.The sodium ions and chloride ions are not joined to each other, but are attracted to each other by electrostatic attraction. 7.Sodium chloride conducts electricity when melted because there are electrons free to move around. 8.When sodium chloride dissolves in water, the sodium chloride molecules break apart. TRUE FALSE