Question 1

Estimate the pH of 0.10 M Na2HPO4(aq)given pKa1 = 2.12,pKa2 = 7.21,and pKa3 = 12.68 for phosphoric acid.

Accepted Answer

A) 12.68 
B) 9.94 
C) 7.40 
D) 4.67 
E) 2.12 
A) 12.68 
B) 9.94 
C) 7.40 
D) 4.67 
E) 2.12

Question 2

Which of the following is the strongest base?

Accepted Answer

A) methylamine (pKb = 3.44) 
B) morphine (pKb = 5.79) 
C) urea (pKb = 13.90) 
D) ammonia (pKb = 4.75) 
E) pyridine (pKb = 8.75) 
A) methylamine (pKb = 3.44) 
B) morphine (pKb = 5.79) 
C) urea (pKb = 13.90) 
D) ammonia (pKb = 4.75) 
E) pyridine (pKb = 8.75)

Question 3

Of the following,which is not a Lewis acid?

Accepted Answer

A) H3O+ 
B) SO3 
C) NO2F1F1F1S1F1F1F10 
D) BF3  
E) None of the above. 
A) H3O+ 
B) SO3 
C) NO2F1F1F1S1F1F1F10 
D) BF3  
E) None of the above.

Question 4

What is the pH of 0.025 M (CH3)3N(aq)(Kb = 6.5 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F105)?

Accepted Answer

A) 11.91 
B) 12.40 
C) 11.11 
D) 8.29 
E) 9.81 
A) 11.91 
B) 12.40 
C) 11.11 
D) 8.29 
E) 9.81

Question 5

A 0.0010 M solution of a weak acid,HA,with Ka = 2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1010 produces [H3O+] F1F1F106 M.Which of the following equations can be used to determine [H3O+]?

Accepted Answer

A) The acid is so weak that the pH is about 7. 
B) [H3O+]2 + Ka [H3O+] F1F1F1S1F1F1F10 [HA]initialKa = 0 
C) [H3O+] = (Kw + Ka[HA]initial)½ 
D) [H3O+] = [HA]initial  
E) [H3O+] = (Ka[HA]initial)½ 
A) The acid is so weak that the pH is about 7. 
B) [H3O+]2 + Ka [H3O+] F1F1F1S1F1F1F10 [HA]initialKa = 0 
C) [H3O+] = (Kw + Ka[HA]initial)½ 
D) [H3O+] = [HA]initial  
E) [H3O+] = (Ka[HA]initial)½

Question 6

What is the [H+] for a solution labeled "0.0500 M H2SO3(aq)" if pKa1 = 1.81,and pKa2 = 6.91?

Accepted Answer

A) 0.021 M 
B) 0.029 M 
C) 0.015 M 
D) 0.025 M 
E) 0.050 M 
A) 0.021 M 
B) 0.029 M 
C) 0.015 M 
D) 0.025 M 
E) 0.050 M

Question 7

The amino acid alanine,HOOC-CH(CH3)NH3+,has Ka1 = 4.5 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 and Ka2 = 1.4 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1010.Calculate F1F1F1S1F1F1F10(F1F1F1S1F1F1F10OOC-CH(CH3)NH3+)at pH 10.

Accepted Answer

A) 0.42 
B) 0.29 
C) 1.0 
D) 0 
E) 0.58 
A) 0.42 
B) 0.29 
C) 1.0 
D) 0 
E) 0.58

Question 8

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right.   Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

Accepted Answer

A) NaHSO4  
B) KF 
C) HNO2  
D) CH3NH2  
E) (CH3)3NHCl 
A) NaHSO4  
B) KF 
C) HNO2  
D) CH3NH2  
E) (CH3)3NHCl

Question 9

The pH of 0.010 M H3PO4(aq)is 2.24.Estimate the concentration of HPO42F1F1F1S1F1F1F10 in the solution.For H3PO4,the values of Ka1,Ka2,and Ka3 are 7.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103,6.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108,and 2.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013,respectively.

Accepted Answer

A) 5.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
B) 7.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
C) 0.010 M 
D) 6.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108 M 
E) 2.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013 M 
A) 5.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
B) 7.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
C) 0.010 M 
D) 6.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108 M 
E) 2.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013 M

Question 10

The pH of a 0.0050 M aqueous solution of calcium hydroxide is

Accepted Answer

A) 11.40 
B) 2.00 
C) 12.00 
D) 12.70 
E) 11.70 
A) 11.40 
B) 2.00 
C) 12.00 
D) 12.70 
E) 11.70

Question 11

Of the following,which is the strongest acid?

Accepted Answer

A) CH3COOH (pKa = 4.75) 
B) HNO2 (pKa = 3.37) 
C) HF (pKa = 3.45) 
D) HCN (pKa = 9.31) 
E) HIO3 (pKa = 0.77) 
A) CH3COOH (pKa = 4.75) 
B) HNO2 (pKa = 3.37) 
C) HF (pKa = 3.45) 
D) HCN (pKa = 9.31) 
E) HIO3 (pKa = 0.77)

Question 12

Which of the following is the weakest acid?

Accepted Answer

A) HNO3 
B) HClO4 
C) HClO2 
D) HClO 
A) HNO3 
B) HClO4 
C) HClO2 
D) HClO

Question 13

Bond polarity tends to dominate the trend of acid strengths for binary acids of elements of the same period.True or false?

Accepted Answer

A) True 
 B)False

Question 14

Calculate the equilibrium constant for the reaction HSF1F1F1S1F1F1F10(aq)+ H2O(l)↔ H2S(aq)+ OHF1F1F1S1F1F1F10(aq),
Given Ka1 = 1.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107 and Ka2 = 7.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1015 for H2S.

Accepted Answer

A) 1.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107  
B) 7.7 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108  
C) 9.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1022  
D) 7.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1015  
E) 1.4 
A) 1.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107  
B) 7.7 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108  
C) 9.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1022  
D) 7.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1015  
E) 1.4

Question 15

If pKa1 and pKa2 for H2S are 6.88 and 14.15,respectively,calculate the equilibrium constant for the reaction below: H2S(aq)+ 2H2O(l)↔ 2H3O+(aq)+ S2F1F1F1S1F1F1F10(aq)

Accepted Answer

A) 1.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107  
B) 1.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107  
C) 7.7 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108  
D) 9.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1022  
E) 7.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1015  
A) 1.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107  
B) 1.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F107  
C) 7.7 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108  
D) 9.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1022  
E) 7.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1015

Question 16

The pH of 0.80 M benzenesulfonic acid is 0.51.What is the percentage ionization of benzenesulfonic acid?

Accepted Answer

A) 25% 
B) 39% 
C) 51% 
D) 5.0% 
E) 64% 
A) 25% 
B) 39% 
C) 51% 
D) 5.0% 
E) 64%

Question 17

If the value of Kb for pyridine is 1.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F109,calculate the equilibrium constant for C5H5NH+(aq)+ H2O(l)↔ C5H5N(aq)+ H3O+(aq)

Accepted Answer

A) (F1F1F1S1F1F1F101.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F109 ) 
B) 1.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1016  
C) 5.6 F1F1F1S1F1F1F10 108  
D) 1.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F109  
E) 5.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F106  
A) (F1F1F1S1F1F1F101.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F109 ) 
B) 1.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1016  
C) 5.6 F1F1F1S1F1F1F10 108  
D) 1.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F109  
E) 5.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F106

Question 18

In a solution labeled "0.0018 M barium hydroxide" what is the molarity of OHF1F1F1S1F1F1F10?

Accepted Answer

A) 0.0018 M 
B) 0.00090 M 
C) 0.0036 M 
D) 0.0072 M 
E) None of the above. 
A) 0.0018 M 
B) 0.00090 M 
C) 0.0036 M 
D) 0.0072 M 
E) None of the above.

Question 19

The pH of 0.010 M H3PO4(aq)is 2.24; estimate the concentration of PO43F1F1F1S1F1F1F10 in the solution.For H3PO4,the values of Ka1,Ka2,and Ka3 are 7.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103,6.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108,and 2.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013,respectively.

Accepted Answer

A) 5.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
B) 2.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013 M 
C) 7.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
D) 6.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108 M 
E) 2.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1018 M 
A) 5.8 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
B) 2.1 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1013 M 
C) 7.6 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F103 M 
D) 6.2 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F108 M 
E) 2.3 F1F1F1S1F1F1F10 10F1F1F1S1F1F1F1018 M

Question 20

Which of the following is not a Lewis acid?

Accepted Answer

A) H3O+ 
B) SO3 
C) NO2F1F1F1S1F1F1F10 
D) BF3 
E) BCl3 
A) H3O+ 
B) SO3 
C) NO2F1F1F1S1F1F1F10 
D) BF3 
E) BCl3

Estimate the pH of 0.10 M Na₂HPO₄(aq)given pK_a1 = 2.12,pK_a2 = 7.21,and pK_a3 = 12.68 for phosphoric acid.

Which of the following is the strongest base?

Of the following,which is not a Lewis acid?

What is the pH of 0.025 M (CH₃)₃N(aq)(K_b = 6.5  10^⁵)?

A 0.0010 M solution of a weak acid,HA,with K_a = 2  10^¹⁰ produces [H₃O⁺] < 10^⁶ M.Which of the following equations can be used to determine [H₃O⁺]?

What is the [H⁺] for a solution labeled "0.0500 M H₂SO₃(aq)" if pK_a1 = 1.81,and pK_a2 = 6.91?

The amino acid alanine,HOOC-CH(CH₃)NH₃⁺,has K_a1 = 4.5  10^³ and K_a2 = 1.4  10^¹⁰.Calculate (^OOC-CH(CH₃)NH₃⁺)at pH 10.

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

The pH of 0.010 M H₃PO₄(aq)is 2.24.Estimate the concentration of HPO₄²^ in the solution.For H₃PO₄,the values of K_a1,K_a2,and K_a3 are 7.6  10^³,6.2  10^⁸,and 2.1  10^¹³,respectively.

The pH of a 0.0050 M aqueous solution of calcium hydroxide is

Of the following,which is the strongest acid?

Which of the following is the weakest acid?

Bond polarity tends to dominate the trend of acid strengths for binary acids of elements of the same period.True or false?

Calculate the equilibrium constant for the reaction HS^(aq)+ H₂O(l)↔ H₂S(aq)+ OH^(aq), Given K_a1 = 1.3  10^⁷ and K_a2 = 7.1  10^¹⁵ for H₂S.

If pK_a1 and pK_a2 for H₂S are 6.88 and 14.15,respectively,calculate the equilibrium constant for the reaction below: H₂S(aq)+ 2H₂O(l)↔ 2H₃O⁺(aq)+ S²^(aq)

The pH of 0.80 M benzenesulfonic acid is 0.51.What is the percentage ionization of benzenesulfonic acid?

If the value of K_b for pyridine is 1.8  10^⁹,calculate the equilibrium constant for C₅H₅NH⁺(aq)+ H₂O(l)↔ C₅H₅N(aq)+ H₃O⁺(aq)

In a solution labeled "0.0018 M barium hydroxide" what is the molarity of OH^?

The pH of 0.010 M H₃PO₄(aq)is 2.24; estimate the concentration of PO₄³^ in the solution.For H₃PO₄,the values of K_a1,K_a2,and K_a3 are 7.6  10^³,6.2  10^⁸,and 2.1  10^¹³,respectively.

Which of the following is not a Lewis acid?

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Exam 12: Acids and Bases

Estimate the pH of 0.10 M Na2HPO4(aq)given pKa1 = 2.12,pKa2 = 7.21,and pKa3 = 12.68 for phosphoric acid.

Which of the following is the strongest base?

Of the following,which is not a Lewis acid?

What is the pH of 0.025 M (CH3)3N(aq)(Kb = 6.5  105)?

A 0.0010 M solution of a weak acid,HA,with Ka = 2  1010 produces [H3O+] < 106 M.Which of the following equations can be used to determine [H3O+]?

What is the [H+] for a solution labeled "0.0500 M H2SO3(aq)" if pKa1 = 1.81,and pKa2 = 6.91?

The amino acid alanine,HOOC-CH(CH3)NH3+,has Ka1 = 4.5  103 and Ka2 = 1.4  1010.Calculate (OOC-CH(CH3)NH3+)at pH 10.

The following 0.1 M aqueous solutions are arranged in order of increasing pH,with the highest pH on the far right. Which one of the following 0.10 M aqueous solutions should be placed in the empty box?

The pH of 0.010 M H3PO4(aq)is 2.24.Estimate the concentration of HPO42 in the solution.For H3PO4,the values of Ka1,Ka2,and Ka3 are 7.6  103,6.2  108,and 2.1  1013,respectively.

The pH of a 0.0050 M aqueous solution of calcium hydroxide is

Of the following,which is the strongest acid?

Which of the following is the weakest acid?

Bond polarity tends to dominate the trend of acid strengths for binary acids of elements of the same period.True or false?

Calculate the equilibrium constant for the reaction HS(aq)+ H2O(l)↔ H2S(aq)+ OH(aq), Given Ka1 = 1.3  107 and Ka2 = 7.1  1015 for H2S.

If pKa1 and pKa2 for H2S are 6.88 and 14.15,respectively,calculate the equilibrium constant for the reaction below: H2S(aq)+ 2H2O(l)↔ 2H3O+(aq)+ S2(aq)

The pH of 0.80 M benzenesulfonic acid is 0.51.What is the percentage ionization of benzenesulfonic acid?

If the value of Kb for pyridine is 1.8  109,calculate the equilibrium constant for C5H5NH+(aq)+ H2O(l)↔ C5H5N(aq)+ H3O+(aq)

In a solution labeled "0.0018 M barium hydroxide" what is the molarity of OH?

The pH of 0.010 M H3PO4(aq)is 2.24; estimate the concentration of PO43 in the solution.For H3PO4,the values of Ka1,Ka2,and Ka3 are 7.6  103,6.2  108,and 2.1  1013,respectively.

Which of the following is not a Lewis acid?

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Chemical Kinetics

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Nuclear Chemistry

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Estimate the pH of 0.10 M Na₂HPO₄(aq)given pK_a1 = 2.12,pK_a2 = 7.21,and pK_a3 = 12.68 for phosphoric acid.

What is the pH of 0.025 M (CH₃)₃N(aq)(K_b = 6.5  10^⁵)?

A 0.0010 M solution of a weak acid,HA,with K_a = 2  10^¹⁰ produces [H₃O⁺] < 10^⁶ M.Which of the following equations can be used to determine [H₃O⁺]?

What is the [H⁺] for a solution labeled "0.0500 M H₂SO₃(aq)" if pK_a1 = 1.81,and pK_a2 = 6.91?

The amino acid alanine,HOOC-CH(CH₃)NH₃⁺,has K_a1 = 4.5  10^³ and K_a2 = 1.4  10^¹⁰.Calculate (^OOC-CH(CH₃)NH₃⁺)at pH 10.

The pH of 0.010 M H₃PO₄(aq)is 2.24.Estimate the concentration of HPO₄²^ in the solution.For H₃PO₄,the values of K_a1,K_a2,and K_a3 are 7.6  10^³,6.2  10^⁸,and 2.1  10^¹³,respectively.

Calculate the equilibrium constant for the reaction HS^(aq)+ H₂O(l)↔ H₂S(aq)+ OH^(aq), Given K_a1 = 1.3  10^⁷ and K_a2 = 7.1  10^¹⁵ for H₂S.

If pK_a1 and pK_a2 for H₂S are 6.88 and 14.15,respectively,calculate the equilibrium constant for the reaction below: H₂S(aq)+ 2H₂O(l)↔ 2H₃O⁺(aq)+ S²^(aq)

If the value of K_b for pyridine is 1.8  10^⁹,calculate the equilibrium constant for C₅H₅NH⁺(aq)+ H₂O(l)↔ C₅H₅N(aq)+ H₃O⁺(aq)

In a solution labeled "0.0018 M barium hydroxide" what is the molarity of OH^?

The pH of 0.010 M H₃PO₄(aq)is 2.24; estimate the concentration of PO₄³^ in the solution.For H₃PO₄,the values of K_a1,K_a2,and K_a3 are 7.6  10^³,6.2  10^⁸,and 2.1  10^¹³,respectively.