Transcript Learning Check pH2

Learning Check pH2
The [OH-] of a solution is 5 x 10 -5 M.
What is the [H3O+ ] of the solution?
1)
2 x 10- 5 M
2)
1 x 1010 M
3)
2 x 10-10 M
Solution pH2
The [OH-] of a water solution is 5 x 10-5 M.
What is the [H3O+] in the solution?
[ H3O+] = 1.0 x 10 -14
5 x 10- 5
On some calculators:
1.0 EE +/- 14
 5 EE +/- 5 = 2 x 10 -10 M
Learning Check pH3
A.The [OH-] when [H3O+ ] of 1 x 10- 4 M
1) 1 x 10-6 M
2) 1 x 10-8 M
3) 1 x 10-10 M
B.The [H3O+] when [OH- ] of 5 x 10-9 M
1) 1 x 10- 6 M
2) 2 x 10- 6 M
3) 2 x 10-7 M
Solution pH3
Kw = [H3O+ ][OH-] = 1.0 x 10 14
A. (3) [OH- ] =
1.0 x 10 -14 = 1.0 x 10 -10
1.0 x 10- 4
B. (2) [H3O+] = 1.0 x 10 -14 = 2 x 10 - 6
5 x 10- 9
pH
 Indicates the acidity [H3O+] of the solution
 pH = - log [H3O+]
 From the French pouvoir hydrogene
(“hydrogen power” or power of
hydrogen)
pH
In the expression for [H3O+]
1 x 10-exponent
the exponent = pH
[H3O+] = 1 x 10-pH M
pH Range
0
1
2
3 4 5
6
7 8 9 10 11 12 13 14
Basic
Acidic
Neutral
[H+]>[OH-]
[H+] = [OH-]
[OH-]>[H+]
Some [H3O+] and pH
[H3O+]
pH
1 x 10-5 M
5
1 x 10-9 M
9
1 x 10-11 M
11
pH of Some Common Acids
gastric juice
1.0
lemon juice
2.3
vinegar
2.8
orange juice
3.5
coffee
5.0
milk
6.6
pH of Some Common Bases
blood
7.4
tears
7.4
seawater
8.4
milk of magnesia
10.6
household ammonia
11.0