1. Unit 6: TOXINS Solutions & Kinetics!

2. What do you think the word “solution” means in chemistry (not “solution” as in “answer”)?
Discuss your ideas with the people at your group and then write your answer down.

3. Vocabulary Aqueous solution: solution where water is the solvent
Solute
Solvent
substance which is dissolved
The minority substance in the mixture
dissolving substance
The majority substance in the mixture
Aqueous solution: solution where water is the solvent

4. Example: You have a beaker of 1000 mL of propanol and decide to dissolve some calcium chloride in it.
Which is the solute? _______________
Which is the solvent? ______________
CaCl2
Propanol

5. Solvents Most of the time WATER is our solvent
However, there are many important non-water solvents!
Paint Thinner (Turpentine, C10H16)
Nail Polish remover (Acetone, C3H6O)
Dry cleaning (perchloroethylene,C2Cl4)
*a carcinogen

6. MIXTURES!
Mixture: Two or more substances mixed together that retain their original properties (in other words, no chemical bonds form between the two or more molecules)

7. Types of Mixtures “different” throughout the same throughout
HOMOGENEOUS
HETEROGENEOUS
“different” throughout
the same throughout
SOLUTIONS are always homogeneous!

8. Shampoo?
Homogeneous

9. Chunky Picante Salsa?
Heterogeneous

10. Chex Mix?
Heterogeneous

11. Salt water?
Homogeneous

12. Summary Soluble Insoluble It dissolves.
homogeneous- transparent solution
Insoluble
It doesn’t dissolve.
heterogeneous- can have different “parts”

13. Remember . . . Like dissolves like. Polar Non-polar
Polar substances will dissolve in _________ substances.
Non-polar substances will dissolve in _____________ substances.
Polar
Non-polar
New: Ionic substances will dissolve in POLAR substances.

14. No, iodine is non-polar and water is polar
Would iodine crystals dissolve in water?
No, iodine is non-polar and water is polar

15. Yes, iodine is non-polar and paint thinner is non-polar
Would iodine crystals dissolve in paint thinner?
Yes, iodine is non-polar and paint thinner is non-polar

16. Concentration: The amount of solute for a specified amount of solution.
(A common measure of concentration is moles of solute per liter of solution (m/L).)

17. MOLARITY!
Moles of solute
Liters of solution

18. You have 8 moles of HCl and you pour it into 2 liters of water
You have 8 moles of HCl and you pour it into 2 liters of water. What concentration of HCl did you produce?
8 moles HCl
4 mol/L OR
4 M =
2 liters solution

19. Which acid would you rather have spill on your arm?

20. 1 mole/L would be less concentrated than 12 moles/L!

21. LABEL EACH MOLECULE AS POLAR COVALENT, NON-POLAR COVALENT or IONIC
LABEL EACH MOLECULE AS POLAR COVALENT, NON-POLAR COVALENT or IONIC. Covalent: 2 or more non-metals Ionic: metal and a non-metal

22. Oil, C20H42
Ethanol, C2H6O
NON-POLAR Covalent
POLAR Covalent

23. Copper (II) Chloride, CuCl2
Calcium carbonate, CaCO3
IONIC
IONIC

24. Molecular Structures
Citric Acid, C6H8O6
POLAR Covalent

25. WARNING: ACTS NON-POLAR TODAY
Molecular Structures
Styrofoam
Acetone, C3H6O
NON-POLAR, Covalent
POLAR, Covalent
WARNING: ACTS NON-POLAR TODAY

26. Intermolecular Forces Review
Intermolecular Forces: the attraction holding 2 or more molecules together
Types: Dispersion, Dipole-Dipole, Hydrogen bonding
Bonds: the force holding 2 or more atoms together within a molecule

27. Types of Inter-Molecular Forces (IMF)
(see posters for review!)
Dispersion: (weakest)
found in non-polar molecules
Dipole: (stronger)
attracts polar molecules together
Hydrogen bond: (strongest)
molecules with O-H, N-H, or F-H bonds

28. Which substances dissolved in water?
Non-polar molecules?
vegetable oil, styrofoam
Polar molecules?
ethanol, citric acid
Ionic compounds?
copper chloride, calcium carbonate

29. Like dissolves Like Water is polar
This means that a water molecule has both a positive and a negative side (these are the two “poles”)
Water dissolves ionic and polar molecules best
Ionic molecules contain positive and negative ions
Polar molecules have positive and negative “sides”

30. Like dissolves Like Polar dissolves polar.
Ethanol and water
Nonpolar dissolves nonpolar.
Hexane and oil
Nonpolar will NOT dissolve with polar
oil (nonpolar) and water (polar) will NOT mix

31. Dissolving an ionic solid in H2O
NaCl (aq)  Na+ (aq) + Cl- (aq)
The ions will break apart, each ion is attracted to the polar water molecules

32. When molecules dissolve…
When molecules dissolve…. Intermolecular forces attract molecules to water

33. Note: when covalent molecules dissolve…
Note: when covalent molecules dissolve…. The molecules do NOT break apart into individual atoms or ions

34. Nonpolar Compounds DO NOT dissolve in water
Dipole attractions (between water molecules)
Non-polar substance
(ex: oil)

35. How does soap work? Soap has both a
POLAR/CHARGED part (attracts to water)
NONPOLAR part (attracts to oil)
So, soap allows us to “dissolve” oil in water and clean our hands!