1. Hydrogen Bonding and The Nature of Solutions

2. Hydrogen Bonding
A hydrogen atom that is bonded to a highly electronegative atom (such as oxygen) is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule

3. Hydrogen Bonding
Due to the small size of the hydrogen atom, it can become very close to an unshared pair of electrons on the nearby molecule
Compounds with this type of force have unusually high boiling points.

4. Hydrogen bonding in H2O
Hydrogen bonding is what gives water its unusual properties such as :
High boiling point/ high melting point
Great surface tension
Amphoteric (can be an acid or a base.)
High polarity
Known as “the universal solvent”

5. Hydrogen bonding in H2O

6. A. Definitions Solution - homogeneous mixture
Solute - substance being dissolved
Solvent – substance doing the disolving

7. A. Definitions
Solvent - H2O
Solute - KMnO4

8. B. Solvation First... Then... Solvation – the process of dissolving
solute particles are surrounded by solvent particles
First...
solute particles are separated and pulled into solution
Then...

9. B. Solvation Non- Electrolyte Weak Electrolyte Strong Electrolyte+
sugar - +
acetic acid - +
salt
Non-
Electrolyte
Weak
Electrolyte
Strong
Electrolyte
solute exists as
molecules only
solute exists as
ions and
molecules
solute exists as
ions only
DISSOCIATION
IONIZATION

10. NaCl(s)  Na+(aq) + Cl–(aq)
B. Solvation
Dissociation
separation of an ionic solid into aqueous ions
NaCl(s)  Na+(aq) + Cl–(aq)

11. HNO3(aq) + H2O(l)  H3O+(aq) + NO3–(aq)
B. Solvation
Ionization
breaking apart of some polar molecules into aqueous ions
HNO3(aq) + H2O(l)  H3O+(aq) + NO3–(aq)

12. B. Solvation C6H12O6(s)  C6H12O6(aq) Molecular Solvation
molecules stay intact
C6H12O6(s)  C6H12O6(aq)

13. B. Solvation
“Like Dissolves Like”
NONPOLAR
POLAR

14. B. Solvation Soap/Detergent polar “head” with long nonpolar “tail”
dissolves nonpolar grease in polar water

15. C. Solubility UNSATURATED SOLUTION more solute dissolves
no more solute dissolves
SUPERSATURATED SOLUTION
becomes unstable, crystals form
concentration

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

17. C. Solubility Solubility Curve
shows the dependence of solubility on temperature

18. C. Solubility Solids are more soluble at... high temperatures.
Gases are more soluble at...
low temperatures &
high pressures (Henry’s Law).
EX: nitrogen narcosis, the “bends,” soda