1. A. Definitions Solution - homogeneous mixture
Solute - substance being dissolved
Solvent - present in greater amount. The substance doing the dissolving

2. Solutions Soluble – Something that can be dissolved into solution
Ex. Salt is soluble in water
Insoluble – Something that cannot be dissolved
Ex. Oil is insoluble in water
“magic sand” is insoluble in water.

3. Water as a Universal Solvent
Because water dissolves SO MANY COMPOUNDS and MOLECULES, Water is usually referred to as the UNIVERSAL SOLVENT.

4. water

5. Water Molecule The water molecules
is made up of one oxygen atom and 2 hydrogen atoms,
covalently bonded into a V-shaped molecule. (the water is bent

6. Structure of Water
Oxygen is more electronegative than hydrogen (it has a stronger attraction for the shared electrons).
This causes an uneven distribution of charge within each covalent bond since electrons spend more time near O than H. The bond is said to be polar.

7. A polar bond results from the unequal sharing of electrons between atoms in a molecule.

8. Polarity of water
Polarity of H2O molecule results in attraction of H2O molecules to each other.
partial "+“charge of the H atoms attracted to partial "-" charge of the O atoms in another H2O molecule

9. Like dissolves like
Since water is a polar molecule it dissolves other polar molecules AND ionic compounds

10. Non-polar molecules such as oil, and gasoline do not dissolve in water

11. But what does dissolving means?

12. Solvation
occurs at the surface of the solute
solvent particles surround solute particles (+/- attraction)
solute particles are pulled into solution

14. Like Dissolves Like
NONPOLAR
POLAR

15. Guided Practice Lets see how much we have learned today!!!!!
(See solution Chem practice questions)

16. FACTORS THAT AFFECT THE RATE OF DISSOLVING!!!

17. Rate of Solution Solids dissolve faster... more stirring
small particle size (increased surface area)
high temperature

18. Gases dissolve faster...
no shaking or stirring
high pressure
low temperature

19. Concentration Concentrated solution large amount of solute
Dilute solution
small amount of solute

20. A. Concentration UNSATURATED SOLUTION more solute dissolves
no more solute dissolves
SUPERSATURATED SOLUTION
becomes unstable, crystals form
concentration

21. B. Solubility Solubility
maximum grams of solute that will dissolve in 100 g of solvent at a given temperature
varies with temperature
based on a saturated solution

22. B. Solubility Solubility Curve
shows the dependence of solubility on temperature

23. B. Solubility Solids are more soluble at... high temperatures.
Gases are more soluble at...
low temperatures.
high pressures (Henry’s Law).

24. B. Electrolytes Electrolyte Weak Electrolyte Non- Electrolyte+
salt - +
acetic acid - +
sugar
Electrolyte
Weak
Electrolyte
Non-
Electrolyte
solute exists as
ions only
solute exists as
ions and
molecules
solute exists as
molecules only

25. B. Electrolytes Dissociation
separation of +/- ions when an ionic compound dissolves in water

26. B. Electrolytes Ionization
breaking apart of polar covalent molecules into ions when dissolving in water

27. C. Colligative Properties
properties of solutions that depend only on solute concentration
Freezing Point Depression
solutes lower the f.p. of a solvent
Boiling Point Elevation
solutes raise the b.p. of a solvent

28. C. Colligative Properties
Effect increases as the solute concentration increases.
Uses:
antifreeze
making ice cream
salting icy roads

29. Mixtures that are not Solutions
Suspensions – A temporary mixture in which the particle eventually settle
Colloid- A mixture that has large particles like milk, egg whites, mayonnaise. These often look homogeneous or the same throughout
You can tell a colloid by the Tyndall Effect or the scattering of light it exhibits