in aqueous solution… in aqueous solution… hcl (aq) h + (aq) + cl - (aq) acids acids increase...
TRANSCRIPT
• In aqueous solution…In aqueous solution…
HCl(aq) H+(aq)+ Cl-(aq)
AcidsAcids increase hydrogen ion concentration [H+]
Courtesy Christy Johannesson www.nisd.net/communicationsarts/pages/chem
BasesBases increase hydroxide ion concentration [OH-]
KOH (aq) K+(aq)+ OH-
(aq)
H2O can function as both an ACID and a
BASE.
Equilibrium constant for water = Kw
Kw = [H+] [OH-] = 1.00 x 10-14 at 25 oC
pH
pOH
[H+]
[OH-]
pH + pOH = 14
pH = -log[H+]
[H+] = 10-pH
pOH = -log[OH-]
[OH-] = 10-pOH
Kw = [H+] [OH-] = 1 x10-14
OH-
H+OH-
OH-H+
H+
[H+] = [OH-] [H+] > [OH-] [H+] < [OH-] acidic
solutionneutralsolution
basicsolution
co
nc
en
trat
ion
(m
ole
s/L
)
10-14
10-7
10-1
Timberlake, Chemistry 7th Edition, page 332
pH = 3
pH = 7
pH = 12
pH + pOH = 14pH + 11.09 = 14
Solution is acidic
pH = 14 – 11.09 = 2.91
Solution is basic
Kw = [H+] [OH-] = 1.0 x10-14
1.0 x10-14 = [3.3 x 10-10] [OH-]
[OH-] = 3.0 x 10-5 M
pH = - log [H+] = -log [0.240M H+]
pH = 0.620
pH = - log [H+]
4.60 = -log [H+]
[H+] = 2.51 x 10-5 M2nd log -4.6
You can check your answer by working backwards.
pH = - log [2.51x10-5 M]
pH = 4.60
10- 4.60
Timberlake, Chemistry 7th Edition, page 335
1.0 MHCl0
gastricjuice1.6
vinegar2.8
carbonated beverage3.0
orange3.5
apple juice3.8
tomato4.2
lemonjuice2.2 coffee
5.0
bread5.5
soil5.5
potato5.8
urine6.0
milk6.4
water (pure)7.0
drinking water7.2
blood7.4
detergents8.0 - 9.0
bile8.0
seawater8.5
milk of magnesia10.5
ammonia11.0
bleach12.0
1.0 MNaOH(lye)14.0
8 9 10 11 12 14133 4 5 621 70
acidic neutral basic[H+] = [OH-]
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
6 5 .
7
3 4 1 2