1. Solutions: More Vocab

2. Soluble soluble: capable of being dissolved
a substance that dissolves in another substance is said to be soluble in that substance

3. Insoluble
a substance that does not dissolve in another substance

4. solubility: maximum amount substance that dissolves in given amount of another substance
LIMITED amount solute that dissolves in given amount solvent
affected by temperature and pressure

5. rate of dissolving is different from amount that will dissolve!
rate is how fast
amount is how much

6. factors that affect the rate of dissolving:
temperature
stirring or agitation
amount of surface area of solute
amount of solute already dissolved

7. Dissolving
dissolving is physical change

8. dissolved covalent substances: produce MOLECULES in solution
source
dissolved covalent substances:
produce MOLECULES in solution
C6H12O6(s) + H2O(l) C6H12O6(aq)

9. dissolved ionic substances:
produce IONS in solution
NaCl(s)+H2O(l)  Na+1(aq) + Cl-1(aq)

10. Solvation interaction between solvent molecules & solute particles
solute particles surrounded by solvent particles during dissolving process
solute particles may be:
ions
polar molecules
non-polar molecules
solvent molecules may be:
polar
non-polar

11. Solvation in different systems.

12. Hydration describes solvent-solute interaction when solvent is water
hydration of chloride ion
also called: molecule-ion interaction

13. Molecule-ion interaction
Solute-solvent interaction
must be greater than:
interaction between
solute particles
for dissolving to occur

14. Solubility
amount solute dissolved in specific amount solvent at given TEMPERATURE and PRESSURE
units:
grams solute per 100 grams solvent

15. Solubility Curves of Selected SOLIDS
solubility traces for most solids have (+)’ve slopes;
the hotter the solvent, the more solute dissolves

16. Solubility Curves of Selected GASES
solubility traces for all gases have
(–)’ve slopes
Do you know why most fish prefer cold water?

17. Vocabulary Interlude miscible: two liquids that WILL MIX
together in any amounts
water and ethanol are miscible in all proportions
immiscible: liquids that will NOT MIX
oil and water are immiscible

18. Oil & H2O are immiscible

19. Types of Solutions Matter Mixtures Elements Compounds Pure Substances
Homogeneous
Mixtures =
Solutions
Heterogeneous
Elements
Compounds
Conduct current
Nonconductor

20. Electricity What do you need to conduct electricity?
mobile, positively charged particles!!!!

21. Vocabulary Interlude electrolyte: non-electrolyte:
substance that dissolves in water to form solution that conducts electricity
ions present in solution
non-electrolyte:
substance that dissolves in water to form solution that does not conduct electricity
neutral molecules present in solution

22. electrolyte vs. non-electrolyte
Which solution conducts a current?

23. Dilute vs. Concentrated
large amounts of solute present
dilute
small amounts of solute present

24. the stronger the color, the more concentrated the solution
Which solution is most dilute?
most concentrated?
How can you tell?
the stronger the color, the more concentrated the solution

25. to dilute a solution: add MORE solvent

26. Which solution is more concentrated?
More dilute?
What can you say about the # of solute particles in pictures
b and c?
the # is the same!

27. Unsaturated Solution
less than maximum amount solute that will dissolve at given T and P

28. Saturated Solution no more solute will dissolve at given T & P
solubility = amount solute required to form saturated solution

29. The solution is saturated when the solute stops dissolving

30. Dynamic Equilibrium in Saturated Solution
microscopic level: rate dissolving = rate recrystallization
macroscopic level: no apparent change

31. Supersaturated Solution
contains more solute than saturated solution
VERY unstable
have to be clever to make these (need to use heat)

32. Testing for saturation:
add additional crystal of solute into solution and see what happens

33. 3 possible results: unsaturated solution saturated solution
crystal dissolves:
crystal sinks to bottom of solution:
Bam! Suddenly have
lots of solid solute
in beaker:
saturated solution
supersaturated solution

34. What kind of solution was this?

35. How do terms saturated, unsaturated & supersaturated fit in with the solubility curves?

36. saturated solns:
any point on trace line
(max solute dissolved)
supersaturated solns:
all points above trace lines (more than max)
unsaturated solutions:
all points below trace lines (less than max)

37. A B C D characterize points
A, B, C, D with respect to KNO3 trace line
(dilute, concentrated, saturated, unsaturated, or supersaturated) A B
A,C = concentrated & supersaturated
B=concentrated & saturated C D
D = dilute &
unsaturated

38. Solubility Graphs traces: have positive or negative slopes
most solids have positive slope
the hotter the water, the more solute dissolves
The colder the water, the less solute dissolves
all gases have negative slope
the hotter the water, the less gas dissolves
The colder the water, the more gas dissolves

39. Summary of Dissolving occurs at surface of solid
interaction: between solute & solvent
interaction called “solvation”
interaction called “hydration” (if solvent is H2O)
involves: change in energy