pH of Common Substances

Timberlake, Chemistry 7th Edition, page 335

Calculating pH• pH = -log [H+]

• So if [H+] = 1x10-5

pH = - log (1x10-5 ) = 5

• Calculate the pH if[H+] = 1 x 10-2 M pH =

[H+] = 3.0 x 10-6 M pH =

[H+] = 8.2 x 10-6 M pH =

Convert pH to [H+]

• 10-pH = [H+]

• If pH = 5, 10-pH = 10-5 = 0.000 01 = 1 x 10-5 M

• Calculate the [H+] if pH = 2.37 [H+] =

pH = 11.05 [H+] =

pH = 6.50 [H+] =

pH of Common Substance

14 1 x 10-14 1 x 10-0 0 13 1 x 10-13 1 x 10-1 1 12 1 x 10-12 1 x 10-2 2 11 1 x 10-11 1 x 10-3 3 10 1 x 10-10 1 x 10-4 4 9 1 x 10-9 1 x 10-5 5 8 1 x 10-8 1 x 10-6 6

6 1 x 10-6 1 x 10-8 8 5 1 x 10-5 1 x 10-9 9 4 1 x 10-4 1 x 10-10 10 3 1 x 10-3 1 x 10-11 11 2 1 x 10-2 1 x 10-12 12 1 1 x 10-1 1 x 10-13 13 0 1 x 100 1 x 10-14 14

NaOH, 0.1 MHousehold bleachHousehold ammonia

Lime waterMilk of magnesia

Borax

Baking sodaEgg white, seawaterHuman blood, tearsMilkSalivaRain

Black coffeeBananaTomatoesWineCola, vinegarLemon juice

Gastric juice

Mor

e ba

sic

Mor

e ac

idic

pH [H1+] [OH1-] pOH

7 1 x 10-7 1 x 10-7 7

pOH

• pOH= -log [OH-]• 10-pOH = [OH-]

• So if [OH-] = 4 x 10-3 M

pOH = -log (4 x 10-3) = 2.397 = 2.40

• pH + pOH = 14

[H+] [OH-] pH pOH A / B / N

3.2 x 10-3

1.26 x 10-5

10.3

7.89

Complete this for homework…

[H+] [OH-] pH pOH A / B / N

2.5 x 10-6

1.0 x 10-12

12.3

0.9