1. Solutions Like dissolves Like

2. Describe the terms electronegativity and polarity Explain the solution process of simple ionic and covalent compounds Include: dissociation, hydration, heat of solution Additional KEY Terms PolarNon-polar Solvation

3. Electronegativity The attraction an atom has for the shared pair of electrons in a bond The most electronegative element is fluorine = 4.0 The least electronegative element is cesium = 0.7 In a compound, the atom with the higher electronegativity pulls the SHARED electrons closer

4. POLAR COVALENT Unequal sharing of bonding electrons Creates positive and negative dipoles at opposite parts of compound Bigger EN difference - more polar the bond ++ HCl δ+δ+ δ-δ-

5. NON-POLAR COVALENT Equal sharing of bonding electrons NO dipoles – no permanent charges Small EN difference Diatomics and compounds of C and H are non-polar Cl chlorine gas C C C H H H H H H H H C H H H H methane propane

6. IONIC Give/take of electrons between M and NM Creates charged IONS REALLY big EN difference + -

8. Some molecules can contain polar bonds, but because of the shape are considered to be non-polar molecules.

9. Dissolving vs. Dissociating Sugar vs. Salt

10. **The general dissolving rule is like dissolves like.** Solvation: the process of dissolving… Particles of solute will dissolve IF it is more attracted to the solvent particles than to itself

11. There are 3 steps to the dissolving process: 1.Solute particles must break apart. Requires energy (lattice energy) to break IMFs 2.Solvent particles spread apart to make room. Requires energy to reduce solvent IMFs 3.Solute and solvent particles come together. Releases energy Heat of solution - the sum of the energy changes for (usually endothermic overall)

12. Water a polar molecule If a solute is attracted to water it will dissolve When water is the solvent – hydration **The general dissolving rule is like dissolves like.**

13. H Cl H O H H O H H H O H H O H δ-δ- δ+δ+ δ-δ- δ+δ+ δ+δ+ DISSOLVE √ δ-δ- δ+δ+

14. polar solvent ionic solute H O H H O H H O H H O H + - δ-δ- δ+δ+ δ+δ+ Na Cl Na Cl DISSOLVE √

15. polar solvent polar solute H O H H H H H C C H O H H H H H C C H O H H O H δ-δ- δ+δ+ δ-δ- δ+δ+ δ-δ- δ+δ+ DISSOLVE √

16. Charged solutes (polar covalent or ionic) are attracted to charged solvents to various degrees *The more soluble a solute is, the more attracted to the solvent it must be* Uncharged particles (non-polar) are only soluble in uncharged solvents **The general dissolving rule is like dissolves like**

17. polar solvent non-polar solute H O H H O H δ-δ- δ+δ+ δ-δ- δ+δ+ C H H H H C H H H H DISSOLVE No dipoles Nothing to attract too

18. H C C H C H H H H non-polar solvent non-polar solute C H H H H H C C H DISSOLVE √ No dipoles No attraction or repulsion - Free to mix

19. SOAP Has a polar end and a non-polar tail Non-polar tail attracts oil Polar head attracts water This allows the ball of grease to "dissolve" in the water H O H H O H H O H H O H

21. CAN YOU / HAVE YOU? Describe the terms electronegativity and polarity Explain the solution process of simple ionic and covalent compounds Include: dissociation, hydration, heat of solution Additional KEY Terms PolarNon-polar Solvation