Question

Acid Strength III

Calculate the pH and percent ionization of each solution below. Rank the aqueous solutions of the acids below from highest pH to lowest pH and separately rank the percent ionization from highest to lowest.

A 0.10 M CH3COOH (acetic acid)

B 0.020 M CH3COOH

C 0.010 M HNO3 (nitric acid)

D 1.5 M HNO3

E 0.050 M HClO (hypochlorous acid)

F 0.20 M CH3CH2COOH (propanoic acid)

Highest pH 1_______ 2_______ 3_______ 4_______ 5_______ 6_______ Lowest pH

Highest %ionized 1_______ 2_______ 3_______ 4_______ 5_______ 6_______ Lowest % ionized

Explain your reasoning below (Show Calculations and include the reaction!)

Answer 1

Highest pH to lowest pH

1) 0.050M HClO 2) 0.20Mpropnoic acid 3) 0.010M nitric acid 4)0.10M acetic acid 5) 0.020M acetic aicd

6) 1.5M HNo3

HClO is the weakest acid with pKa = 7.46,thus pH = 1/2 [pKa -log C] = 3.079

propanoic acid with pKa = 4.88, and p H = 2.09

0.10 acetic acid pKa = 4.74 , pH = 1.875

0.020M acetic acid , pH = 1.52

0.010M nitric acid , pH =2.0

1.5M HNo3 pH <0

Highest percent of ionixzation folows the reverse order aspH = -log [H+] and [H+] = C(degree of ionization)

1) 1.5M HNo3 2) 0.020M acetic aicd 3)0.10M acetic acid 4)0.010M nitric acid 5) 0.20Mpropnoic acid

6)0.050M HClO