1. SOLUBILITY

2. Solubility Solubility how many grams of solute that will dissolve in 100 g of solvent to make it saturated at a given temperature

3. Dissolution- the rate at which a substance dissolves

4. FACTORS AFFECTING SOLUBILITY

5. Polarity Factors Affecting Solubility Temperature Surface Area Stirring Pressure

6. Particle size – area of solute particles exposed to the action of the solvent particles. Increase in surface area of the solute particles, solubility increases Example: fine table salt dissolves faster than rock salt SURFACE AREA

7. Stirring or Agitation increases the solubility of solid solute particles in a solvent. Because it speeds up the contact between the surface of the solute and the solvent particles AGITATION

8. Effect of Temperature on Solubility of Solids and Liquids Generally, increasing the temperature will increase solubility of solids and liquids. Application of heat - solvent molecules move faster and come in contact frequently with the solute particles, increasing solubility.

9. Solubility Curves LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World, 1996, page 517 0 10 20 30 40 50 60 70 80 90 100 Solubility vs. Temperature Solubility (grams of solute/100 g H 2 O) KI KCl 20 10 30 40 50 60 70 80 90 110 120 130 140 100 NaNO 3 KNO 3 HClNH 4 Cl NH 3 NaCl KClO 3 SO 2 shows the dependence of solubility on temperature gases solids

10. But increasing temperature will lower the solubility of gases (the gas will escape from solution, going back to the gas phase). Effect of Temperature on Solubility of Solids and Liquids

11. Figure 13.18

12. ToTo Sol. ToTo Solids dissolved in liquids Gases dissolved in liquids As T o, solubility

13. Thermal pollution: if lakes get too warm, CO 2 and O 2 become less soluble and are not available for plants or animals. Warm Pop Making Connections

14. The Effect of Pressure on the Solubility of Gases Pressure has no effect on the solubility of solids and liquids but has a strong effect on the solubility of gases. The solubility of gases increases when the pressure above the gas is increased. In other words, more gas will dissolve when pressure is increased. This is known as HENRY’S LAW (William Henry, English chemist).

15. Pressure Effects Figure 13.14: Factors Affecting Solubility

16. Henry’s Law S g = kP g where S g is the solubility of the gas; k is the Henry’s law constant for that gas in that solvent; P g is the partial pressure of the gas above the liquid.

17. Nitrogen narcosis, the “bends” Soda Making Connections http://www.youtube.com/watch?v=LfCOnGHheok&feature=fvst

18. Solutions How does a solid dissolve into a liquid? What ‘drives’ the dissolution process?

19. Polarity Solute – Solvent Interactions Intramolecular Bonding Intermolecular Bonding

20. Intramolecular Bonding Intramolecular bonding refers to the chemical bonding that holds atoms together within a molecule of a compound Covalent bonding and ionic bonding are the two main types of intramolecular bonding

21. Ionic bonding involves the transfer of valence electrons from one atom to another. The electrostatic attraction between opposite charged ions holds the molecule (formula unit) together. An example is sodium chloride, NaCl, which involves the attraction between Na + and Cl - ions.

22. IONIC BONDING

23.  Covalent bonding involves the sharing of valence electrons between two atoms. Eg.covalent bonding holds hydrogen and oxygen atoms together to form a water molecule, H 2 O. POLAR- unequal sharing of electrons NON POLAR – equal sharing of electrons

24. COVALENT BONDING

25. NON POLAR MOLECULE Nonpolar molecules either have no positive and negative ends, because the bonds making up the molecule are nonpolar, or because the entire outer "edge" is negative while the core of the molecule is positive (or vice versa), thus having no oppositely charged ends.

26. POLAR MOLECULE A polar molecule will have one end of the molecule bearing a partial positive charge while another end carries a partial negative charge. Polar molecules must contain polar bonds.

27. The oxygen end of the molecule has a partial negative charge (δ-), while the hydrogen end is partially positive (δ+).

28. Intermolecular Bonds occur between molecules

29. How Does a Solution Form? Solvent molecules cluster around the solute particles. If the intermolecular attraction between the solvent and solute is stronger than between the solute –solute or solvent-solvent molecules, then a solution forms.

30. “like dissolves like” Two substances with similar intermolecular forces are likely to be soluble in each other. non-polar molecules are soluble in non-polar solvents CCl 4 in C 6 H 6 polar molecules are soluble in polar solvents C 2 H 5 OH in H 2 O ionic compounds are more soluble in polar solvents NaCl in H 2 O or NH 3 (l) 12.2

31. SOLUTEPOLAR SOLVENT NONPOLAR SOLVENT IonicSolubleInsoluble PolarSolubleInsoluble NonpolarInsolublesoluble

32. Vitamins Water Soluble – Vitamin C – Must be replenished regularly Fat Soluble – Can overdose (liver damage, hair loss, blurred vision, numbness) – Vitamin A – Can be ingested periodically, stored in body fat Making Connections

33. Factors Affecting Solubility Vitamin A is soluble in nonpolar compounds (like fats). Vitamin C is soluble in water.

34. Watch video and write down explanation on sheet provided. How Salt Dissolves? ION-POLE ATTRACTION

36. How Salt Dissolves? ION-POLE ATTRACTION Each ion in the solute is surrounded by the partial positive and negative solvent molecules in the water. Solute is pulled out of its lattice and solvent molecules spread the solute out throughout the solution.