Acids                Quiz #5         pH calculations for Strong and Weak Acids    

 

1.         The 1.0 M acidic solution with the highest pH is

            A.        H2S

            B         HNO2

            C.        HNO3

            D.        H3BO3

 

2.         At 25 oC, the equation representing the ionization of water is

            A         H2O + H2O ⇄ 2H2 + O2

            B.        H2O + H2O ⇄ H2O2    + H2

                    C.        H2O + H2O ⇄ 4H+ + 2O2-    

            D.        H2O + H2O ⇄ H3O+ +OH-     

 

3.         The pH of a 0.3 M solution of NH3 is approximately

            A.        14.0

            B.        11.0

            C.        6.0

            D.        3.0

 

4.         The pH of an aqueous solution is 4.32. The [OH-] is

            A.        6.4 x 10-1 M

            B.        4.8 x 10-5 M

            C.        2.1 x 10-10 M

            D.        1.6 x 10-14 M

 

5.         The pH of an aqueous solution is 10.32. The [OH-] is

            A.        5.0 x 10-12 M

            B.        2.0 x 10-11 M

            C.        4.8 x 10-11 M

            D.        2.1 x 10-4 M

 

6.         The pH of a 0.025 M HClO4 solution is

            A.        0.94

            B.        1.60

            C.        12.40

            D.        13.06

 

7.         Consider the following equilibrium

                        H2O(l) ⇄ H2O(l) ⇄ H3O+(aq) + OH-(aq)          

            The equilibrium constant for this system is referred to as

            A.        Kw     

            B.        Ka   

            C.        Kb 

            D.        Ksp  

8.         The [H3O-] in a solution of pH 0.60 is

            A.        4.0 x 10-14 M

            B.        2.2 x 10-1 M

            C.        2.5 x 10-1 M

            D.        6.0 x 10-1 M

 

9.         A solution is prepared by adding 100 mL of 10 M of HCl to a 1 litre volumetric

            flask and filling it to the mark with water. The pH of this solution is

 

            A.        -1

            B.        0

            C.        1

            D.        7

 

10.       The approximate pH of a 0.06 M solution of CH3COOH is

            A.        1

            B.        3

            C.        11

            D.        13

 

11.       The [OH-] is greater than the [H3O+] in

            A.        HCl(aq)

            B.        NH3(aq)

            C.        H2O(aq)

            D.        CH3COOH(aq)

 

12.       The pH of 0.15 M HCl is

            A.        0.15

            B.        0.71

            C.        0.82

            D.        13.18

 

13.       Which of the following equations correctly relates pH and [H3O+] ?

            A.        pH= log [H3O+]

            B.        pH= 14 -  [H3O+]

            C.        pH= -log [H3O+]

            D.        pH= pKw – [H3O+]

 

14.       The pH of 0.20 M HNO3 is

            A.        0.20

            B.        0.63

            C.        0.70

            D.        1.58

 

15.       The [OH-] in 0.050 M HNO3 at 25oC is

            A.        5.0 x 10-16 M

            B.        1.0 x 10-14 M

            C.        2.0 x 10-13 M

            D.        5.0 x 10-2 M

 

16.       What is the approximate pH of a 1.0 M solution of the salt NH4Cl?

            A.        0.0

            B.        5.0

            C.        7.0

            D.        10.0

 

17.       What is the approximate pH of a 1.0 M solution of the salt NH3?

            A.        2.0

            B.        5.0

            C.        7.0

            D.        10.0

 

18.       What is the approximate pH of a 1.0 M solution of the salt NaHCO3?

            A.        2.0

            B.        5.0

            C.        7.0

            D.        9.0

 

19.       What is the approximate pH of a 1.0 M solution of the salt AlCl3?

            A.        0.0

            B.        3.0

            C.        7.0

            D.        9.0

 

20.       What is the approximate pH of a 1.0 M solution of the salt NaHSO4?

            A.        0.0

            B.        3.0

            C.        7.0

            D.        9.0

 

21.       Which of the following is a definition of pH?

            A.        pH  =  +Log[H3O+]

            B.        pH  =  -Log[OH-]

            C.        pH  =  -Log[H3O+]

            D.        pH  =  pOH  +  pKw

 

22.       What is the mass of NaOH required to prepare 100.0 mL of NaOH(aq) that has a

            pH = 13.62 ?

            A.        0.38 g

            B.        0.42 g

            C.        1.67 g

            D.        0.14 g

23.       What is the [KOH] in a KOH solution that has a pH =12.00?

            A.        0.010 M

            B.        0.56 M

            C.        2.0 M

            D.        2.0  x  10-12 M

 

24.       What is the [H3O+] in 0.70 M HCN ?

            A.        0.70 M

            B.        1.9  x  10-5 M

            C.        1.0  x  10-6 M

            D.        2.4  x  10-10 M

 

25.       What is the value of pKw for water at 25 0C ?

            A.        10  x  10-14

            B.        10  x  10-7

            C.        7.00

            D.        14.00

 

26.       What pH would most likely result when CO2 dissolves naturally in rainwater?

            A.        3.5

            B.        6.5

            C.        7.2

            D.        7.8

 

27.       What is the pOH of 0.05 M Ba(OH)2 ?

            A.        1.0

            B.        1.3

            C.        12.7

            D.        13.0

 

28.       What is the pH of 0.5 M Sr(OH)2 ?

            A.        0.0

            B.        0.3

            C.        12.7

            D.        14.0

 

29.       Which of the following statements is true for an acidic solution at 25 0C ?

            A.        pH  >  7.0

            B.        pOH  <  7.0

            C.        [H3O+]  <  [OH-]

            D.        [H3O+]  >  [OH-]

 

30.       What is the [OH-] in 0.025 M HCl ?

            A.        2.5  x  10-16 M

            B.        4.0  x 10-13 M

            C.        2.5  x  10-2 M

            D.        1.6 M