Acid - Base_1_

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					Acids & Bases review
                                                     8. In a 0.050 M solution of a weak monoprotic
1. Which oxide forms a basic solution when                acid, [H+]= 1.8 x 10¯3. What is its Ka?
    mixed with water?                                     (A) 3.6 x 10¯2       (C) 6.7 x 10¯5
    (A) K2O              (C) CO2                          (B) 9.0 x 10¯5       (D) 1.6 x 10¯7
    (B) Al2O3            (D) SO3

2. Which 0.1 M solution has the highest pH?          9. According to the Brønsted-Lowry definition, a
    (A) sodium carbonate                                 base is a substance that
    (B) sodium chloride                                  (A) increases the hydroxide ion
    (C) ammonium carbonate                               concentration in water.
    (D) ammonium chloride                                (B) can react with water to form OH¯ ions.
                                                         (C) can donate an electron pair to form a
3. Which is the strongest acid?                          covalent bond.
    (A) acetic acid - (Ka = 1.8 x 10¯5)                  (D) can accept a proton from an acid.
    (B) benzoic acid - (Ka = 6.3 x 10¯5)
    (C) formic acid - (Ka = 1.8 x 10¯4)              10. What is the pH of a 0.02 M solution of
    (D) nitrous acid - (Ka = 6.0 x 10¯4)                 KOH?
                                                         (A) 12.3              (C) 2.0
4. A water solution of sodium carbonate,                 (B) 12.0              (D) 1.7
     Na2CO3, has a pH greater than 7 because
     (A) it contains more carbonate ions than        11. Which couple is not a conjugate acid-base
     water molecules.                                    pair?
     (B) it contains more sodium ions than               (A) HCO3¯ and CO32¯
     carbonate ions.                                     (B) H3O+ and H2O
     (C) sodium ions react with water.                   (C) H2PO4¯ and PO43¯
     (D) carbonate ions react with water.                (D) NH3 and NH2¯

5. According to Brønsted -Lowry Theory, which        12. These acids are listed in order of decreasing
of these species cannot be amphoteric?                    acid strength in water.
     (A) NH4+(aq)         (C) NH2¯(aq)                       HI > HNO2 > CH3COOH > HCN
     (B) NH3(aq)          (D) NH2¯(aq)                    According to the Brønsted-Lowry theory,
                                                          which anion is the weakest base?
6. Which of these acids is the strongest in               (A) I¯                 (C) CH3COO¯
    aqueous solution?                                     (B) NO2¯               (D) CN¯
    (A) H3PO4              (C) HCl
    (B) H2SO3              (D) HOCl                  13. What is the [H+] in a 0.40 M solution of
7. Normal rain water has a pH of 5.6. This is best         Substance Equilibrium Constant, Ka
    explained by the presence of
                                                             HOCl             3.5 x 10¯8
    (A) nitrogen oxides.
    (B) carbon dioxide.                                  (A) 1.4 x 10¯8 M      (C) 1.9 x 10¯4 M
    (C) sulfur oxides.                                   (B) 1.2 x 10¯4 M      (D) 3.7 x 10¯4 M
    (D) particulates.
14. Which of these salts will give a basic           21. When 0.10 M solutions of the solutes;
    solution when added to water?                        HClO4, NH4Br, KOH, KCN, are arranged in
    (A) NH4NO3            (C) Ca(NO3)2                   order in increasing [H+], the correct order is
    (B) NH4C2H3O2         (D) Ca(C2H3O2)2                (A) KOH < KCN < NH4Br < HClO4
                                                         (B) KCN < KOH < HClO4 < NH4Br
15. At 0 °C the ion product constant of water,           (C) HClO4 < NH4Br < KCN < KOH
     Kw, is 1.2 x 10¯15. The pH of pure water at         (D) NH4Br < HClO4 < KOH < KCN
     this temperature is
     (A) 6.88              (C) 7.46                  22. For which titration would the use of
     (B) 7.00              (D) 7.56                      phenolphthalein introduce a significant
16. What is the [H+] in a 0.010 M solution of            Kindicator for phenolphthalein = 1 x 10¯9
    HCN? The equilibrium constant, Ka, for
    HCN equals 6.2 x 10¯10
    (A) 3.6 x 10¯3 M       (C) 1.0 x 10¯7 M
    (B) 2.5 x 10¯6 M       (D) 6.2 x 10¯10 M

17. HCN(aq) + HCO3¯(aq)
                         CN¯(aq) + H2CO3(aq)
     If the value of the equilibrium constant, K,
     is less than 1, what is the strongest base in
     this system?
     (A) HCN                 (C) CN¯
     (B) HCO3¯               (D) H2CO3               23. The titration curves labeled 1 and 2 were
                                                         obtained by titrating equal volumes of two
18. The conjugate acid of the bicarbonate ion,           different acid samples with portions of the
     HCO3¯, in H2O is                                    same sodium hydroxide solution.
     (A) H3O+             (C) OH¯
     (B) CO3 ¯            (D) H2CO3

19. The sodium salt, NaA, of a weak acid is
     dissolved in water and no other substance is
     added. Which of the following statements is
     (A) [H+] = [A¯]      (C) [A¯] = [OH¯]               What conclusions can be drawn about the
     (B) [H ] = [OH¯]     (D) [HA] = [OH¯]               relative concentrations and strengths of
                                                         acids 1 and 2 from these curves?
20. Which of these ions is predicted to produce          (A) The concentrations are the same but acid
    the most acidic solution when dissolved in               1 is weaker than acid 2.
    H2O?                                                 (B) The concentrations are the same but acid
    (A) K+                (C) Co2+                           1 is stronger than acid 2.
    (B) Ba2+              (D) Fe3+                       (C) Acid 1 is the same strength as acid 2, but
                                                             it is less concentrated.
                                                         (D) Acid 1 is the same strength as acid 2, but
                                                             it is more concentrated.

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