2. Warm-Up 12/15/2016
What volume is needed to store 105 grams of helium gas at 202.6kPa and ˚C?

3. Properties of Acids
Acids have the following properties:
a. Sour taste (Example: Lemon juice and vinegar, for example, are both aqueous solutions of acids.
b. Form solutions that are electrolytes ( An ionic compound whose aqueous solution conducts an electric current)

4. c. Can produce H2 gas
d. Are corrosive
e. Generate H+ ions in solutions
CAUTION: You should never attempt to identify an acid or a base by its taste or feel

5. Different Definitions of Acids
Arrehenius Acid: any substance that produces H+ ions
Bronstead-Lowry Acid: is a hydrogen ion donor
Lewis Acid: electron pair acceptor

6. Litmus Test and Other Color Changes
Acids and bases cause certain colored dyes to change color. The most common of these dyes is litmus.
When mixed with an acid, litmus is red.

7. Reactions with Metals and Carbonates
Another characteristic property of an acid is
that it reacts with metals that are more active than hydrogen.
This property explains why acids corrode most metals.
Show how corrosive an Acid can be by doing the Disappearing Can Demo. Need 1 sanded aluminum can, 500 mL of a 2 M HCl(aq), pencil, 600 mL beaker

8. Acidic Hydrogen Atoms
To help distinguish acids from other hydrogen-containing molecules, acidic hydrogen are written first in the formula.
HELPFUL HINT: Any time hydrogen is the first element in a formula of a compound, and it is aqueous then the compound is an acid.

9. Monoprotic Acids
Acids such as acetic acid, HC2H3O2, and hydrochloric acid, HCl, are called monoprotic acids.
Monoprotic acids contain only one acidic hydrogen.

10. Diprotic and Triprotic Acids
All acids that have more than one acidic hydrogen per molecule are called polyprotic acids.
Polyprotic acids with two acidic hydrogens are diprotic acids.

11. Diprotic and Triprotic Acids
Those with three acidic hydrogens are triprotic acids.

12. The Hydronium Ion
When acids dissociate, H+ ions are formed
The H+ ion is attracted to a water molecule and forms a bond
The resulting ion is called a hydronium ion, H3O+

13. Formation of Hydronium Ion
This is a polyatomic ion that can be considered an acidic solution.

14. Begin 1st 4-28-2000 Properties of Bases
Bases have the following properties:
a. Bitter taste
b. Slippery feel
c. Are electrolytes
d. Are corrosive
e. Change the color of an indicator
Begin 1st

15. Different Definitions of Bases
Arrehenius Base: any substance that produces OH- ions
Bronstead-Lowry Base: is a hydrogen ion acceptor
Lewis Base: electron pair donor

16. Example: NaOH, KOH, Ca(OH)2
Behavior of Bases
A base is a substance that produces hydroxide ions, OH –, when it dissolves in water.
Example: NaOH, KOH, Ca(OH)2

17. The dissociation of the base is complete.
Strong Bases
Sodium hydroxide, NaOH, is a strong base because when NaOH dissolves in water, all NaOH formula units dissociate into separate sodium and hydroxide ions.
The dissociation of the base is complete.

18. Weak Bases
Ammonia is a weak base because most of its molecules do not react with water to form ions.
Other examples of bases that produce so few OH– ions that they are considered to be weak bases are Al(OH)3, and Fe(OH)3.

19. Naming Bases
Bases produce hydroxide ions in solutions
Most bases contain (OH-) in the formula
Naming Bases:
The metal’s name plus hydroxide
Example: NaOH

20. Naming Bases Continued
Name the following bases:
1. KOH
2. Mg(OH)2
3. Fe(OH)3

21. Write formulas for the following:
1. Calcium Hydroxide
2. Lithium Hydroxide
3. Silver Hydroxide
Begin 5th 4-28

22. The Dissociation of Water
Water dissociates (breaks down) to produce H+ and (OH)- ions
H2O (l)  H+ (aq) + (OH)- (aq)
Pure water contains the same amount of H+ and (OH)- ions

23. The Dissociation of Water
In pure water, the concentration of H+ times the concentration of (OH)- always equals 1.0 x 10-14
[H+ ] * [(OH)- ] = 1 .0 x 10-14

24. The Dissociation of Water
When [H+ ] = [(OH)- ], the solution is neutral
When [H+ ] > [(OH)- ], the solution is acidic
When [H+ ] < [(OH)- ], the solution is basic