1. Complete the table below.

 

[H+1] mol/L

[OH-1] mol/L

pH

pOH

Neutral, acidic, or basic

A

1x 10-7

[ OH-] = 10 –pOH

= 10 –7

pH=-log[H+]

-log[1x 10-7]

=7.0

pH + pOH =14

pOH = 14 - 7.0

= 7.0

Neutral

B

1.5 x 10-3

6.7 x 10-12

2.82

11.18

Acidic

C

3.0 x 10-10

3.33 x 10-5

9.52

4.48

Basic

D

0.1

1 x 10-13

1.0

13.0

Acidic

E

[H+] = 10 –pH

10 –7.30 =

5.0 x 10 –8

2.0 x 10-7

pH + pOH =14

pH = 14.00 -6.70 =7.30

pOH=-log[ OH-]=

-log(2.0 x 10-7)

= 6.70

Slightly basic

F

2.5 x 10 –13

4.0 x 10-2

12.6

1.4

basic

G

6.3 x 10 –6

1.5 x 10-9

5.20

8.80

Acidic

H

2.0 x 10 -14

0.5

13.7

0.3

basic

I

[H+] = 10 –pH

=10 –2.0 = 0.01

1.0 x 10 –12

Stomach acid (2.0)

12.0

acidic

J

1.7 x 10 –7

5.9 x 10 –8

Milk (6.77)

7.23

Slightly acidic

K

1 x 10 –12

1 x 10 –2

Household cleaner (12.0)

2.0

Basic

L

6.3 x 10 –13

[ OH-] = 10 –pOH = 10 –1.80 =

1.6 x 10 –2

12.20

1.80

Basic

M

5.5 x 10 –9

1.8 x 10 –6

8.26

Baking soda (5.74)

Basic

N

3.2 x 10 –3

3.2 x 10 –12

2.5

Lemon juice (11.5)

Acidic
  1. Order the solutions from #2 (A to F only) from the strongest to the weakest acid. Explain which values you used and why?

D – B – A – E – C – F

 Lowest pH corresponds to the strongest acid because it corresponds to the highest hydrogen ion concentration.

  1. In an aqueous solution, the H+1 (aq) concentration is 2.8 x 10-4 M. What is the concentration of OH-1 (aq)?

[ OH-][H+] = 10-14

2.8 x 10-4 [ OH-] = 10-14

[ OH-] = 3.6 x 10-11 M

  1. In an aqueous solution in which the OH-1 (aq) concentration is 1.0 x 10-7 M, what is the concentration of H+1 (aq)?

[ OH-][H+] = 10-14

1.0 x 10-7[H+] = 10-14

[H+] = 1.0 x 10-7 M

  1. The pH of a sample of human blood was measured to be 7.41 at 25 0C. Calculate pOH, [H+1]aq, and [OH-1]aq for the sample.

[H+] =10 –pH =10 –7.41 = 3.9 x 10-8 mol/L

pH + pOH = 14

pOH = 14.00 – 7.41

pOH = 6.59

[ OH-] = 10 –pOH =10 –6.59 =

= 2.6 x 10-7 mol/L

6.         Identify 2 Brφnsted-Lowry bases and two acids from each of the following:

a.         HCO3- (aq)              +          NH3(aq)             CO3-2(aq)                     +          NH4+(aq)

            acid(donates H+           Base                            base(in reverse rxn)                acid

 to NH3)

b.         HSO4- (aq)         +          H2PO4- (aq)        H3PO4            +          SO42- (aq)

acid(donates H+           Base                            acid                             base

 to H2PO4-)

7.         Show how CH3COOH can act as an acid in water.

CH3COOH      +          H2O     CH3COO-      +          H3O+