Factors affecting Solubility

1. Factors affecting Solubility

2. Activity 1 • Solutions are found at home and in the environment. • Solutions are made up of solutes and solvents. • Solutions can be solid, liquid or gas. • Solutions can be naturally occurring or manufactured.

3. Activity 2 • Solutions have only one phase, thus, a uniform appearance. • The components of a solution cannot be separated through filtration because their particles are very small that they can pass through the holes of the filter paper.

4. Activity 3 • A saturated solution is a solution that contains the maximum amount of solute that the solvent can dissolve. • The presence of excess solute that can no longer dissolve is the evidence that a solution is saturated. • An unsaturated solution is a solution that contains less solute than the maximum amount that the solvent can dissolve.

5. Concentrations of solutions • percent by volume – amount of solute in a given volume of solution (g/100 mL) • percent by mass – amount of solute in a given mass of solvent (g/100g)

6. What could affect the solubility of solutes in solutions? Add a teaspoon of salt Add a teaspoon of salt Not stirred Stirred

7. Why would the solute dissolve faster when the solution is stirred?

8. Why would the solute dissolve faster when the solution is stirred?

9. Why would the solute dissolve faster when the solution is stirred?

10. Why would the solute dissolve faster when the solution is stirred?

11. Why would the solute dissolve faster when the solution is stirred?

12. Why would the solute dissolve faster when the solution is stirred?

13. Stirring causes the particles of solute and solvent to move faster increasing the chances of contact.

14. Activity 4 • Which will dissolve faster – crystals of table salt or the same amount of crushed table salt?

15. Procedures Add 50 mL of water into 2 identical containers. Add 5 grams of rock salt to one container and 5 grams iodized salt to the other container. Independent variable Record the time it takes the salt to dissolve in each of the containers. Dependent variable

16. What makes the crushed salt dissolve faster than the crystals of salt? crystal of table salt crushed table salt

22. Smaller particles have more edges and corners where the solvent can be in contact. Thus, the smallerthe particle of salt, the easier it mixes with water.

23. The Coffee Problem • Why do people stir coffee in water after they have added sugar?

24. Parallel Investigations • Activity 5: How fast does coffee dissolve in hot water? In cold water? [G1-G5] • Activity 6: Which dissolves faster in hot and cold water: sugar or salt? [G6-G10]

25. Prepare a lab sheet that will answer the problem assigned to your group. • Do not forget to formulate a hypothesis for your problem. • Bring the materials that you will need for the investigation next session.