Question 1

The fractional composition diagram for the amino acid alanine is given below.  Write the structure of the dominant species at pH 1,6,and 12,respectively.

Accepted Answer

HOOC-CH(CH₃)NH₃⁺,^-OOC-CH(CH₃)NH₃⁺ and ^-OOC-CH(CH₃)NH₂.

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

Question 3

Which of the following is the strongest acid?

Accepted Answer

A)  CH3CH2OH
B)  CH3COOH
C)  CHCl2COOH
D)  CH2ClCOOH
E)  CCl3COOH E

Question 4

The conjugate base of ammonia is

Accepted Answer

A)  NH2OH.
B)  NH2-.
C)  NH4+.
D)  NH3.
E)  OH-.

Question 5

The pH of 0.010 M aniline(aq)is 8.32.What is the percentage aniline protonated?

Accepted Answer

A)  2.1%
B)  0.69%
C)  0.021%
D)  0.12%
E)  0.21%

Question 6

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

Accepted Answer

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

Question 7

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)  NaCN
B)  CH3COOH
C)  KNO2 
D)  NaBr
E)  NaHSO4

Question 8

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)

Question 9

For a solution labeled "0.10 M H3PO4(aq),"

Accepted Answer

A)  [H2PO4-] is greater than 0.10 M.
B)  [H+] = 0.30 M.
C)  [PO43-] = 0.10 M.
D)  [H+] = 0.10 M.
E)  [H+] is less than 0.10 M.

Question 10

When CaO(s)is dissolved in water,which of the following is true?

Accepted Answer

A)  The solution contains O2-(aq) ,OH-(aq) ,and Ca2+(aq) .
B)  The solution contains CaO(aq) .
C)  CaO(s) does not dissolve in water.
D)  The solution contains O2-(aq) and Ca2+(aq) .
E)  The solution contains OH-(aq) and Ca2+(aq) .

Question 11

Which of the following is the weakest acid?

Accepted Answer

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

Question 12

Write the autoprotolysis reaction for liquid ammonia.

Accepted Answer

The answer of Write the autoprotolysis reaction for liquid ammonia....

Question 13

The Ka of phenol is 1.3 * 10-10.For a solution labeled "1.0 * 10-3 M aqueous phenol,"

Accepted Answer

A)  [H3O+] = [H3O+]2/[phenol]initial.
B)  [H3O+] initial.
C)  [H3O+] > 10-6.
D)  pH ~ 4.
E)  Kw/[H3O+] >> [phenol]initial.

Question 14

The amino acid alanine,HOOC-CH(CH3)NH3+,has Ka1 = 4.5 * 10-3 and Ka2 = 1.4 * 10-10.Calculate $\alpha$(-OOC-CH(CH3)NH3+)at pH 3.

Accepted Answer

A)  0
B)  0.82
C)  0.18
D)  0.29
E)  0.58

Question 15

What is the conjugate base of H2PO4- ?

Accepted Answer

A)  HPO42-
B)  OH-
C)  H3PO4
D)  H2PO4-
E)  PO43-

Question 16

All of the following acids have the same strength in water except

Accepted Answer

A)  HNO3
B)  HClO3
C)  HBr
D)  HF

Question 17

The amino acid methionine,HOOC-CH(CH2CH2SCH3)NH3+,has pKa1 = 2.2 and pKa2 = 9.1.If this amino acid is represented by H2L+,the major species at pH 6 is

Accepted Answer

A)  HL
B)  H2L+
C)  L-
D)  HL and L-

Question 18

Strong acids are leveled in water to the strength of the acid H3O+.

Accepted Answer

A) True 
 B)False

Question 19

Write the charge balance equation for a solution that is 0.0010 M phenol(aq).Let phenol be represented by HA(aq).

Accepted Answer

A)  [H3O+] = [OH-]
B)  Kw = [H3O+][OH-]
C)  [H3O+] = [OH-] + [A-]
D)  Ka = Kw/Kb 
E)  0.0010 = [HA] + [A-]

Question 20

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.

Accepted Answer

A)  5.8 * 10-3 M
B)  2.1 * 10-13 M
C)  7.6 * 10-3 M
D)  6.2 * 10-8 M
E)  2.3 * 10-18 M

Exam 12: Acids and Bases

Which of the following is the strongest base?

Which of the following is the strongest acid?

The conjugate base of ammonia is

The pH of 0.010 M aniline(aq) is 8.32.What is the percentage aniline protonated?

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

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?

Of the following,which is the strongest acid?

For a solution labeled "0.10 M H₃PO₄(aq) ,"

When CaO(s) is dissolved in water,which of the following is true?

Which of the following is the weakest acid?

Write the autoprotolysis reaction for liquid ammonia.

The K_a of phenol is 1.3 * 10^-10.For a solution labeled "1.0 * 10^-3 M aqueous phenol,"

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

What is the conjugate base of H₂PO₄^- ?

All of the following acids have the same strength in water except

The amino acid methionine,HOOC-CH(CH₂CH₂SCH₃) NH₃⁺,has pK_a1 = 2.2 and pK_a2 = 9.1.If this amino acid is represented by H₂L⁺,the major species at pH 6 is

Strong acids are leveled in water to the strength of the acid H₃O⁺.

Write the charge balance equation for a solution that is 0.0010 M phenol(aq) .Let phenol be represented by HA(aq) .

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.

Exam 12: Acids and Bases

The fractional composition diagram for the amino acid alanine is given below. Write the structure of the dominant species at pH 1,6,and 12,respectively.

Which of the following is the strongest base?

Which of the following is the strongest acid?

The conjugate base of ammonia is

The pH of 0.010 M aniline(aq) is 8.32.What is the percentage aniline protonated?

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

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?

Of the following,which is the strongest acid?

For a solution labeled "0.10 M H3PO4(aq) ,"

When CaO(s) is dissolved in water,which of the following is true?

Which of the following is the weakest acid?

Write the autoprotolysis reaction for liquid ammonia.

The Ka of phenol is 1.3 * 10-10.For a solution labeled "1.0 * 10-3 M aqueous phenol,"

The amino acid alanine,HOOC-CH(CH3) NH3+,has Ka1 = 4.5 * 10-3 and Ka2 = 1.4 * 10-10.Calculate α\alphaα (-OOC-CH(CH3) NH3+) at pH 3.

What is the conjugate base of H2PO4- ?

All of the following acids have the same strength in water except

The amino acid methionine,HOOC-CH(CH2CH2SCH3) NH3+,has pKa1 = 2.2 and pKa2 = 9.1.If this amino acid is represented by H2L+,the major species at pH 6 is

Strong acids are leveled in water to the strength of the acid H3O+.

Write the charge balance equation for a solution that is 0.0010 M phenol(aq) .Let phenol be represented by HA(aq) .

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.

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

For a solution labeled "0.10 M H₃PO₄(aq) ,"

The K_a of phenol is 1.3 * 10^-10.For a solution labeled "1.0 * 10^-3 M aqueous phenol,"

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

What is the conjugate base of H₂PO₄^- ?

The amino acid methionine,HOOC-CH(CH₂CH₂SCH₃) NH₃⁺,has pK_a1 = 2.2 and pK_a2 = 9.1.If this amino acid is represented by H₂L⁺,the major species at pH 6 is

Strong acids are leveled in water to the strength of the acid H₃O⁺.

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.