1. BONDING

2. CONDUCTIVITY The ability of a substance to conduct electricity SOLUBILITY The ability of a substance to dissolve in a liquid (mostly water) Lab Review

3. VOLATILITY The ability of a substance to turn into a gas (or vaporize) MELTING TIME The time it takes for a solid to turn into a liquid Lab Review

4. Bond vs. Compound COMPOUND –two or more elements chemically combined –the substance BOND –the link between elements –what holds the substance together An ionic compound has ionic bonds.

5. Bond vs. Compound

6. Why do atoms bond? To achieve the octet rule  in order to have 8 valence electrons having 8 valence electrons makes them stable or “happy”

7. What are valence electrons? EXACTLY!EXACTLY! valence electrons are the electrons found in the outermost shell of an atom

8. Do you remember this? VALENCE ELECTRONS Group 1 Group 2 Group 13 Group 14 Group 15 Group 16 Group 17 Group 18 1 2 3 4 5 6 7 8

9. Any guess as to what the other electrons are called? core electrons yep!yep!

10. types of bonds Ionic Covalent Metallic

11. IONIC BONDS bond between a metal and a nonmetal to achieve octet for both atoms (e.g. NaCl) involves transfer of electrons

13. IONIC BONDS one atom gains electrons (ANION); the other atom loses electrons (CATION) attraction between oppositely charged ions holds ions together (EMF)

15. IONIC COMPOUNDS ions are arranged so that… –like charges are far from each other –opposite charges are close WHY? –because opposites attract –like charges repel

16. CRYSTAL LATTICE Red spheres represent Cl -1 Yellow spheres represent Na +1 NaCl (table salt) link to table salt crystal

17. IONIC COMPOUNDS high MP/BP since lots of energy is needed to overcome the lattice arrangement gives ionic compounds stability –Low volatility high solubility in water high conductivity lattice arrangement gives specific shape to crystals of compound

18. COVALENT BONDS bond between 2 nonmetals to achieve octet sharing of valence electrons

20. COVALENT BONDS Between 2 nonmetals so…. –both attract e- attraction between nucleus and shared e- holds atoms together usually between atoms w/ high ionization energies and high e- affinities

22. COVALENT COMPOUNDS Two nonmetals make a molecule –combination of atoms formed by covalent bond –ex: CO 2

23. COVALENT COMPOUNDS usually low MP/BP b/c attraction between molecules weak only small amount of energy needed to separate molecules from one another –high volatility do not easily dissolve in water low conductivity

24. NETWORK SOLIDS exception to low MP b/c atoms continue to bond together; get huge molecules e.g. graphite, diamond, glues

25. METALLIC BONDS between 2 metals positive nuclei of atoms surrounded by free-moving electrons all electrons attracted by all the nuclei at the same time

27. METALLIC BONDS »common distribution of electrons throughout metallic crystals WHY? –metals give up electrons easily –low ionization energy & low electron affinity

28. METALLIC SOLIDS sea of electrons accounts for metallic properties: –malleability –ductility –high conductivity –high melting point/boiling point