Acids               Quiz #4                       Anhydrides, Hydrolysis         Answers

 

1.         Which of the following pairs of gases are primarily responsible for producing

            acid rain”?

            A.        O2 and O3

            B.        N2 and O2

            C.         CO and CO2

            D.        NO2 and SO2

 

2.         Sodium potassium tartrate (NaKC4H4O6) is used to raise the pH of fruit during

            processing. In this process, sodium potassium tartrate is being used as a/an

            A.        salt

            B.        acid

            C.        base

            D.        buffer

 

3.         The net ionic equation for the hydrolysis of the salt, Na2S is

            A.        Na2S 2Na+ + S2-

            B.        S2- + H2O OH- + HS+

            C.        Na2S + 2H2O 2NaOH + H2S

            D.        2Na+ + S2- + 2H2O 2Na+ + 2OH- + H2S

 

4.         Which of the following solutions would be acidic?

            A.        sodium acetate

            B.        iron III chloride

            C.        sodium carbonate

            D.        potassium chloride

 

5.         Consider the following salts:

            I.          NaF                 II.         NaClO4            III.       NaHSO4      

            Which of these salts, when dissolved in water, would form a basic solution?

            A.        I only

            B.        I and II only

            C.        II and III only

            D.        I, II and III

 

6.         Which of the following, when dissolved in water, forms a basic solution?

            A.        KCl

            B.        NaClO4

            C.        Na2CO3

            D.        NH4NO3        

 

7.         Which of the following oxides forms a basic solution?

            A.        K2O    

            B.        CO2

            C.        SO3

            D.        NO2

 

8.         Which of the following is amphiprotic in water?

            A.        SO2

            B.        SO32-

            C.        HSO3-

            D.        H2SO3

 

9.         Consider the following equilibrium expression

                        K= [H2S][ OH - ]

                                    [HS-]

            This expression represents the

            A.        Kb for H2S

            B.        Ka for H2S

            C.        Kb for HS-

            D.        Ka for HS-        

 

10.       The reaction of a strong acid with a strong base produces

            A.        A salt and a water    

            B.        A base and an acid

            C.        A metallic oxide and water

            D.        A non-metallic oxide and water

 

11.       Consider the following equilibrium:

            CH3COOH(aq) + NH3(aq) CH3COOH-(aq) NH4+(aq)

            The sequence of Bronsted-Lowry acids and bases is

            A.        acid, base, base, acid

            B.        acid, base, acid, base

            C.        base, acid, base, acid

            D.        base, acid, acid, base

 

12.       The pH range of ‘acid rain’ is often

            A.        3 to 6

            B.        6 to 8

            C.        7 to 9

            D.        10 to 12

 

13.       Water will act as a Bronsted-Lowry acid with

            A.        NH3

            B.        H2S

            C.        HCN

            D.        HNO3       

 

14.       Which of the following is a conjugate acid-base pair?

A.        H3PO4 and PO43-

            B.        H2PO4- and PO43-

            C.        H3PO4 and HPO42-

            D.        H2PO4- and HPO42-

 

15.       What is the net ionic equation for the hydrolysis of NH4Cl ?

            A.        NH4Cl   ®    NH4+    +   Cl-

            B.        Cl-   +    H2O         HCl  +  OH-

            C.        NH4+   +   H2O        H3O+   +   NH3

            D.        NH4+   +   H2O        NH5+   +   OH-

 

16.       What is the approximate pH of the salt NH4Cl?

            A.        0.0

            B.        5.0

            C.        7.0

            D.        9.0

 

17.       Four samples of rain are collected from different geographic regions and the pH is

            measured for each sample.

                                    Sample            pH

                                    1                      2.8

                                    2                      4.0

                                    3                      6.2

                                    4                      6.8

            Which of the above samples would be classified as acid rain?

            A.        1 only

            B.        1 and 2

            C.        1, 2 and 3

            D.        1, 2, 3 and 4

 

18.       Which of the following equations correctly represents the reaction of a metallic

            oxide with water?

            A.        K2O   +   H2O   ®   2KOH

            B.        SO3    +   H2O    ®   H2SO4

            C.        Na2O  +  H2O    ®    Na2O2   +   H2

            D.        NaOH   +   HCl   ®   NaCl   +  HOH

 

19.       Which of the following equations describes the dissociation of the salt,

            ammonium chloride, in water?

            A.        NH4Cl(s)   ®   NH4Cl(aq)

            B.        NH4+(aq)   +   Cl-(aq)   ®   NH4Cl(s)

            C.        NH4Cl(s)   ®  NH4+(aq)   +   Cl-(aq)

            D.        NH4+(aq)  +   H2O(l)    ®   H3O+(aq)   +   NH3(aq)

 

20.       Which of the following salt solutions is acidic?

            A.        NaBr

            B.        AlCl3

            C.        Li2CO3

            D.        NaHCO3

 

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

            A.        3.0

            B.        6.6

            C.        7.0

            D.        7.5

 

22.       Which of the following is the net ionic equation that describes the hydrolysis that

            occurs in a K2CO3 solution?

            A.        K2CO3   ®   2K+   +    CO32-

            B.        2K+   +    CO32-   ®   K2CO3

            C.        CO32-    +   H2O     ®   HCO3-    +    OH-

            D.        K2CO3   +    2H2O   ®   H2CO3   +   2KOH

 

23.       What is the equilibrium expression for the predominant equilibrium in

            NaCN(aq)?

            A.        Kb       =          [Na+][CN-]

                                                [NaCN]          

            B.        Kb       =          [Na+][CN-]

                                                [HCN]

            C.        Kb       =          [HCN][OH-]

                                                [CN-]

            D.        Kb       =          [CN-][OH-]

                                                [HCN]

 

24.       Which of the following salts will be basic?

            A.        KCl

            B.        NH4Cl

            C.        NaBr

            D.        Na2HPO4

 

25.       Which of the following salts will be acidic?

            A.        KCl

            B.        NH4Cl

            C.        NaBr

            D.        Na2HPO4

 

26.       Which is an acid anhydride?

            A.        Na2O

            B.        NaCl

            C.        CO2

            D.        NH4Cl

 

27.       Which formula has the highest pH when in water?

            A.        Na2O

            B.        NaCl

            C.        CO2

            D.        NH4Cl

           

28.       Which formula has the lowest pH when in water?

            A.        Na2O

            B.        NaCl

            C.        FeCl3

            D.        NaHCO3

 

29.       Which formula has the lowest pH when in water?

            A.        NaCN

            B.        Na2HPO4

            C.        NH4Cl

            D.        NaOH

 

30.       Which of the following properties is true for a solution of NaNO3 ?

            A.        It is neutral.

            B.        It is very basic.

            C.        It is slightly basic.

            D.        It is slightly acidic.