Chemistry - A Molecular Science

20.

Consider the following reaction: H

C 2

O 2

+ F 4

1-^ U

HC

O 2

1- + HF K ~ 100 4

a) Which of the two bases is stronger? b)^

Which of the two acids is stronger?

c) What is the approximate value of K

for Ha

C 2

O 2

? 4

21.

The K

of nitrous acid (HNOa

) is 4.0x10 2

-4.

a) Write the reaction to which this equilibrium constant applies.

b)

Express the K

of nitrous acid in terms of concentrations. a

For Exercises 22 and 23, use Equation

12.1 and Table 12.3 to determine the

value of the equilibrium constant

and write the equilibrium constant

expression for each reaction. 22.

a)

H

CO 2

+ SO 3

2- 4

U

HCO

1- 3

+ HSO

1- 4

b)

H^2

S + NH

U 3

HS

1- + NH

1+ 4

c)

2-S

+ H

O 2

U

HS

1- + OH

1-^

23.

a)

NO

1- + H 2

O 2

U

HNO

+ OH 2

1-^

b)

HSO

1- 3

+ HCO

1-^3

U

SO

2- 3

+ H

CO 2

3

c)

H^3

PO

+ OH 4

1-^ U

H

PO 2

1- 4

+ H

O 2

For Exercises 24 and 25, write net equations for the acid-base reactions that occur when the given aqueous

solutions are mixed. Determine the

value of the equilibrium constant. Use single arrows for extensive reactions (K>1000) but double arrows otherwise. 24. a)

HNO

+ NaOH 2

b)

NH

Cl 4

• Na

SO 2

(^3)
c)
NaClO + NaH
PO 2
d) 4
HBr + NH
(^3)
e)
HF + NaCN
f)
H^3
PO

• NaC 4
  H 2
  O 3
  (^2)
  g)
  HClO


• NaH 4
  PO 2
  (^4)

25. a)
    NaC
    H 2
    O 3

• HCN 2
  b)
  KOH + HI
  c)
  H^2
  S + K
  HPO 2
  (^4)
  d)
  NaOH + HClO
  e)
  NaNO


• H 2
  CO 2
  (^3)
  f)
  NH
  Cl + KOH 4
  g)
  HNO
  +KF 3

26. Indicate whether each of the followi
    ng is a strong electrolyte, a weak
    electrolyte, or a nonelectrolyte:
    a)
    HF
    b)
    NaF
    c)^
    HCl
    d)
    CH
    Cl 3


27. 
    

    Indicate whether each of the following
    is a strong electrolyte, a weak
    electrolyte, or a nonelectrolyte:
    a)
    NH
    (^3)
    b)
    C
    H 6
    6
    c) HClO
    d)
    NH
    Cl 4

    
    


28. 
    

    What is meant by a neutral solution?

    
    


29. 
    

    Which of the following compounds could be used to lower the pH of a solution?
    a)
    K^2
    S
    b)
    NH
    Cl 4
    c)
    KCl
    d)
    KHSO
    (^4)
    e)
    HF

    
    


30. 
    

    Indicate whether each of the following so
    lutions is acidic, basic, or neutral:
    a) 0.1 M KNO
    (^2)
    b)
    a solution with a pH of 3
    (^)
    c)^
    a solution in which [OH
    1-] = 10
    -4 M
    e) a solution in which [OH
    1-] = 10
    -8 M

    
    


31. 
    

    Indicate whether each of the following so
    lutions is acidic, basic, or neutral:
    a)^
    0.10 M CH
    COOH 3
    b)
    0.10 M NaCN
    c) 0.10 M KBr
    d)
    a solution in which [H
    O 3
    1+] = 10
    -5 M

    
    


32. 
    

    Indicate which solution in each pair has the
    lower
    pH:
    a)^
    0.1 M HClO
    or 0.2 M HClO 2
    (^2)
    b)
    0.1 M K
    PO 3
    or 0.2 M K 4
    PO 3
    (^4)
    c) 0.1 M HC
    H 2
    O 3
    or 0.1 M HNO 2
    (^2)
    d)
    0.1 M NaOH or water

    
    


33. 
    

    Calculate the pH of each of th
    e following strong acid solutions:
    a)
    0.0032 M HCl
    b)
    0.016 M HCl
    c) 1.5 M HNO
    (^3)

    
    


34. 
    

    Calculate the pH of each of th
    e following strong acid solutions:
    a) 0.80 M HCl
    b)
    2.1x10
    -5 M HClO
    (^4)
    c) 2.1x10
    -3 M HCl

    
    


35. 
    

    Calculate the pH of the following basic solutions:
    a)^
    0.0032 M NaOH
    b)
    0.016 M KOH
    c)^
    0.040 M Ba(OH)
    2

    
    


36. 
    

    Write the expression for K
    for each of the following acids and the a
    chemical equation to which it applies.
    a)
    NH
    1+ 4
    b)
    H^3
    PO
    (^4)
    c)
    HSO
    1-^3
    d)
    CH
    COOH 3
    Chapter 12 Acid-Base Chemistry
    © by
    North
    Carolina
    State
    University