CHEMISTRY 12
pH WORKSHEET
Name: ________________________________ Date: ______________ Block: ______________
1.
2.
3.
Calculate pH and pOH for the following solutions :
a) [H+] = 1.0 x 10-5 M
b) [OH-] = 3.0 x 10-8 M
c) [H+] = 2.5 x 10-2
d) [OH-] = 7.5 x 10-3 M
e) [H+] = 1.2 x 10-14 M
f) [H+] = 6.0 M
Calculate [H+] and [OH-] for the following :
a) pH = 3.0
b) pOH = 2.60
c) pOH = 5.63
d) pH = 7.51
e) pOH = -1.13
f) pH = 0.03
Calculate the pH and the pOH of 0.050 M solutions of the following acids :
a) Perchloric acid, HClO4
b) Carbonic acid, H2CO3
c) Phenol, C6H5OH
d) Aluminum ion, Al(H2O)63+
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4. Boric acid (H3BO3) is commonly used in eyewash solutions in chemistry laboratories to neutralize bases
splashed in the eye. It acts as a monoprotic acid, but the dissociation reaction is slightly different from that of
other acids:
B(OH)3 + H2O < === > B(OH)4- + H+ Ka= 5.8 x 10-10
Calculate the pH of a 0.50 M solution of boric acid.
5. Calculate the pH of the solution formed when 35.0 mL of 1.00 M HCl is mixed with 175.0 mL of 0.25M NaOH.
6. Solution A is prepared with a pH of 2.50, and solution B is prepared with a pH of 5.00. How many times more
acidic is solution A than solution B. Support your answer with calculations.
ANSWERS :
1. pH
a) 5.00
b) 6.48
c) 1.60
d) 11.88
e) 13.92
f) -0.78
3.
a)
b)
c)
d)
g)
pOH
9.00
7.52
12.40
2.12
0.08
14.78
1.30, 12.70
3.83, 11.17
5.59, 8.41
3.08, 10.92
4.15, 9.85
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2.
a)
b)
c)
d)
e)
f)
4.
5.
6.
[H+]
1 x 10-3 M
4.0 x 10-12 M
4.3 x 10-9 M
3.1 x 10-8 M
7.4 x 10-16 M
0.93 M
4.77
12.62
316 x
[OH-]
1 x 10-11 M
2.5 x 10-3 M
2.3 x 10-6 M
3.2 x 10-7 M
13 M
1.1 x 10-14 M