Clark Atlanta University Chemistry Worksheet

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Weak acids include which of the following?

I. HF(aq) II. HI(aq) III. HNO2(aq)
(A) I. only (B) II. only
(C) III. only (D) I. and III. only

Which is not a conjugate acid/base pair?

(A) H2CO3 & CO3
2– (B) HSO4
–
& SO4
2–
(C) H2PO4
–
& HPO4
2– (D) H3O+
& H2O .

Which of the following combinations will produce a
0.4 M NaCl solution?

(A) Mixing 500 mL of 0.4 M NaOH with 500 mL of
0.4 M HCl
(B) Mixing 300 mL of 1.2 M NaOH with 600 mL of
0.6 M HCl
(C) Mixing 500 mL of 0.4 M NaCl solution with 500
mL water
(D) Diluting 400 mL of 0.6 M NaCl with water to a final
volume of 1.0 L

What is the [OH–
] in an aqueous solution which has a
pH = 11.70?
(A) 7.1×10–2 M (B) 5.0×10–3 M
(C) 1.4×10–6 M (D) 2.0×10–12 M

How much Sr(OH)2 • 8 H2O (M = 265.76) is needed to
prepare 250.0 mL of solution in which [OH–
] = 0.100 M?

(A) 3.32 g (B) 6.64 g (C) 9.97 g (D) 13.3 g

0.100 mol of HF (Ka = 6.6 × 10-4
) is added to water to
make 1.00 L of solution. Which statement is correct at
equilibrium?
(A) [H3O+] = [HF] (B) [H3O+] = 0.100 M (C) [HF] > [F–
] (D) [H3O+] > [HF]

What is the percentage ionization of HCOOH molecules
in a 0.10 M solution? [Ka = 1.8 ×10–4]

(A) 4.2% (B) 2.7% (C) 1.8% (D) 1.3%.

In a solution prepared by dissolving 0.1 mol NaNO2 in
1.0 L pure water, which species has the lowest
concentration?

(A) Na+ (B) NO2
– (C) HNO2 (D) H3O+

C6H5OH(aq) + CN–
(aq) æ HCN(aq) + C6H5O
–
(aq)
The equilibrium constant for this reaction is less than 1.
What is the strongest base in this system?

(A) C6H5OH(aq) (B) CN–
(aq) (C) HCN(aq) (D) C6H5O
–
(aq)

Which weak acid has the strongest conjugate base?

(A) acetic acid (Ka = 1.8×10–5) (B) formic acid (Ka = 1.8×10–4) (C) hydrofluoric acid (Ka = 6.8×10–4) (D) propanoic acid (Ka = 5.5×10–5)