Question 1

Which of the following is the weakest acid? A)HNO₃ B)HBr C)HCl D)HF E)HI

Accepted Answer

HF is the weakest acid among the given options as it has the strongest bond between H and F. This results in the ionization of only a small fraction of HF molecules in solution, making it a weak acid.

Question 2

What is the conjugate base of H₂PO₄^- ? A)HPO₄^2- B)OH^- C)H₃PO₄ D)H₂PO₄^- E)PO₄^3-

Accepted Answer

The conjugate base is formed by removing a proton (H+) from the given molecule. The most acidic site in this molecule is the hydrogen attached to the oxygen atom (O) in the sulfonic acid group (HSO3-). Removing this proton would result in the formation of a sulfonate group (SO3-), which is present in option A (HPOSO4-). The other options do not have this group, so they cannot be the correct answer.

Question 3

The conjugate acid of HPO₄^2- is A)HPO₄^2-. B)PO₄^3-. C)H₂PO₄^-. D)H₃O⁺. E)H₃PO₄.

Accepted Answer

The conjugate acid is formed by adding a proton (H+) to the base. In this case, we can identify the base as PO₄²F1F1F1S1^F1F1F10, which has a negative charge. To form the conjugate acid, we remove the negative charge and add a proton: H₂PO₄F1F1F1S1^F1F1F10. Therefore, choice (C) is the correct answer.

Question 4

In the following reaction SO₂(g)+ H₂O(l)$\rightarrow$ H₂SO₃(aq), identify the Lewis acid and base.

Accepted Answer

The answer of In the following reaction SO₂(g)+ H₂O(l)$\rightarrow$ H₂SO₃(aq), identify the...

Question 5

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H₂O-SO₃.In the reaction of the intermediate to produce sulfuric acid, A)water acts both as an acid and a base. B)water acts as a proton donor only. C)water acts as a proton acceptor only. D)the intermediate undergoes an intramolecular rearrangement to form the product.

Accepted Answer

The answer of When sulfur trioxide dissolves in water,sulfuric acid...

Question 6

The pH of a 0.0050 M aqueous solution of calcium hydroxide is
A)11.40
B)2.00
C)12.00
D)12.70
E)11.70

Accepted Answer

Calcium hydroxide is a strong base, so it will dissociate completely in water to form Ca2+ and OH- ions. The pH of a solution of a strong base can be calculated using the formula: pH = 14 - pOH. The pOH of a 0.0050 M solution of calcium hydroxide can be calculated using the formula: pOH = -log[OH-] = -log(2 x 0.0050) = 2.70. Therefore, the pH of the solution is: pH = 14 - 2.70 = 11.30. The closest answer choice is C, 12.00, which is within the margin of experimental error.

Question 7

What is the pK_a of the conjugate acid of hydrazine,given that the pK_b of hydrazine is 5.77? Write the formula of the conjugate acid of hydrazine.

Accepted Answer

The answer of What is the pK_a of the conjugate...

Question 8

The conjugate base of OH^- is A)H⁺. B)OH^-. C)O^2-. D)H₃O⁺. E)H₂O.

Accepted Answer

The conjugate base is formed when an acid loses a proton. In this case, the acid is OHF1F1F1S1^F1F1F10, and the conjugate base will have one less proton. This can be achieved by removing a hydrogen ion (H+) from the acid, which will leave behind its corresponding conjugate base. The resulting species will have all the same atoms as the original acid, but one less proton. The only option that fits this description is C, which is formed by removing the H+ from OHF1F1F1S1^F1F1F10 to form O²F1F1F1S1^F1F1F10.

Question 9

Which of the following is the weakest acid? A)HCN (pK_a = 9.31) B)HIO₃ (pK_a = 0.77) C)HF (pK_a = 3.45) D)CH₃COOH (pK_a = 4.75) E)HNO₂ (pK_a = 3.37)

Accepted Answer

The lower the pKa value, the stronger the acid. HCN has the highest pKa value, so it is the weakest acid.

Question 10

In a solution labeled "0.10 M HNO₃," which of the following is correct? A)[HNO₃] = 0.10 M B)[H₃O⁺] = 0.10 M,[NO₃^-] = 0.10 M C)[H₃O⁺] = 0.090 M,[NO₃^-] = 0.010 M D)[HNO₃] = 0.050 M,[H₃O⁺] = 0.050 M,[NO₃^-] = 0.050 M E)[H₃O⁺] = 0.10 M,[OH^-] = 1.0 * 10^-7 M

Accepted Answer

The answer of In a solution labeled "0.10 M HNO₃,"...

Question 11

The conjugate base of ammonia is A)NH₂OH. B)NH₂^-. C)NH₄⁺. D)NH₃. E)OH^-.

Accepted Answer

The answer of The conjugate base of ammonia is A)NH₂OH. B)NH₂^-. C)NH₄⁺. D)NH₃. E)OH^-....

Question 12

Calculate the hydroxide ion concentration for an aqueous solution that has a pH of 3.45. A)3.2 * 10^-2 M B)0.54 M C)3.5 * 10^-4 M D)2.8 * 10^-11 M E)2.6 * 10^-5 M

Accepted Answer

The pOH can be calculated as 14 - pH = 10.55. The hydroxide ion concentration is then 10^-10.55, which is approximately 2.8 * 10^-11 M.

Question 13

Of the following,which does not have an amphoteric oxide? A)BeO B)PbO C)SnO D)Al₂O₃ E)MgO

Accepted Answer

The answer of Of the following,which does not have an...

Question 14

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

Accepted Answer

In water, strong acids completely dissociate to produce H₃O⁺ ions, and their strength is effectively the same as that of H₃O⁺, as they cannot produce a higher concentration of H₃O⁺ ions than water allows.

Question 15

All of the following are strong bases in water except A)NaHCO₃ B)CaO C)Na₂O D)Na₂SO₄

Accepted Answer

NaHCO3 is a weak base in water. The other options listed are all strong bases in water.

Question 16

Calculate the hydrogen ion concentration for an aqueous solution that has a pH of 3.45. A)0.54 M B)3.5 * 10^-4 M C)2.8 * 10^-11 D)3.2 * 10^-2 M E)1.22 M

Accepted Answer

The hydrogen ion concentration [$\text{H}^+$] in a solution is given by $10^{-\text{pH}}$. For a pH of 3.45, the concentration is $10^{-3.45}$, which matches choice B.

Question 17

Which of the following is the strongest base? A)methylamine (pK_b = 3.44) B)morphine (pK_b = 5.79) C)urea (pK_b = 13.90) D)ammonia (pK_b = 4.75) E)pyridine (pK_b = 8.75)

Accepted Answer

The strength of a base is inversely related to its pK_b value; the lower the pK_b, the stronger the base. Methylamine has the lowest pK_b value among the options, making it the strongest base.

Question 18

What is the conjugate acid of O^2-?

Accepted Answer

The answer of What is the conjugate acid of O^2-?...

Question 19

Write the autoprotolysis reaction for liquid ammonia.

Accepted Answer

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

Question 20

Which of the following produces the strongest conjugate base? A)HF (pK_a = 3.45) B)HClO (pK_a = 7.53) C)HCOOH (pK_a = 3.75) D)CH₃COOH (pK_a = 4.75) E)HIO (pK_a = 10.64)

Accepted Answer

The stronger the acid, the weaker its conjugate base. Therefore, the weaker the pKa, the stronger the acid and the weaker the conjugate base. So, the compound with the highest pKa (weakest acid) is HF, which has the strongest conjugate base. Therefore, Option A is eliminated. Among the remaining answer choices, HIO has the highest pKa (weakest acid), therefore, it has the strongest conjugate base among the given compounds. Therefore, the Answer is E.

Quiz 12: Acids and Bases

Which of the following is the weakest acid?

What is the conjugate base of H₂PO₄^- ?

The conjugate acid of HPO₄^2- is

In the following reaction SO₂(g)+ H₂O(l) $\rightarrow$ H₂SO₃(aq), identify the Lewis acid and base.

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H₂O-SO₃.In the reaction of the intermediate to produce sulfuric acid,

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

What is the pK_a of the conjugate acid of hydrazine,given that the pK_b of hydrazine is 5.77? Write the formula of the conjugate acid of hydrazine.

The conjugate base of OH^- is

Which of the following is the weakest acid?

In a solution labeled "0.10 M HNO₃," which of the following is correct?

The conjugate base of ammonia is

Calculate the hydroxide ion concentration for an aqueous solution that has a pH of 3.45.

Of the following,which does not have an amphoteric oxide?

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

All of the following are strong bases in water except

Calculate the hydrogen ion concentration for an aqueous solution that has a pH of 3.45.

Which of the following is the strongest base?

What is the conjugate acid of O^2-?

Write the autoprotolysis reaction for liquid ammonia.

Which of the following produces the strongest conjugate base?

Quiz 12: Acids and Bases

Which of the following is the weakest acid?

What is the conjugate base of H2PO4- ?

The conjugate acid of HPO42- is

In the following reaction SO2(g)+ H2O(l) →\rightarrow→ H2SO3(aq), identify the Lewis acid and base.

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H2O-SO3.In the reaction of the intermediate to produce sulfuric acid,

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

What is the pKa of the conjugate acid of hydrazine,given that the pKb of hydrazine is 5.77? Write the formula of the conjugate acid of hydrazine.

The conjugate base of OH- is

Which of the following is the weakest acid?

In a solution labeled "0.10 M HNO3," which of the following is correct?

The conjugate base of ammonia is

Calculate the hydroxide ion concentration for an aqueous solution that has a pH of 3.45.

Of the following,which does not have an amphoteric oxide?

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

All of the following are strong bases in water except

Calculate the hydrogen ion concentration for an aqueous solution that has a pH of 3.45.

Which of the following is the strongest base?

What is the conjugate acid of O2-?

Write the autoprotolysis reaction for liquid ammonia.

Which of the following produces the strongest conjugate base?

What is the conjugate base of H₂PO₄^- ?

The conjugate acid of HPO₄^2- is

In the following reaction SO₂(g)+ H₂O(l) $\rightarrow$ H₂SO₃(aq), identify the Lewis acid and base.

When sulfur trioxide dissolves in water,sulfuric acid is produced.An intermediate in the reaction is H₂O-SO₃.In the reaction of the intermediate to produce sulfuric acid,

What is the pK_a of the conjugate acid of hydrazine,given that the pK_b of hydrazine is 5.77? Write the formula of the conjugate acid of hydrazine.

The conjugate base of OH^- is

In a solution labeled "0.10 M HNO₃," which of the following is correct?

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

What is the conjugate acid of O^2-?