Question 1

Which of the following would be the strongest acid?

Accepted Answer

The strength of an acid is inversely related to its pKa value; the lower the pKa, the stronger the acid. Formic acid, with a pKa of 3.75, is the strongest acid listed.

Question 2

What is the pH of a solution that contains three parts acetic acid and one part sodium acetate? The pK for acetic acid is 4.76.

Accepted Answer

The answer of What is the pH of a solution...

Question 3

If the pK values for phosphoric acid are 2.15, 6.82, and 12.38, at what pH would one observe equal amounts of H₂PO₄^- and HPO₄^2-?

Accepted Answer

The answer of If the pK values for phosphoric acid...

Question 4

If the pK values for phosphoric acid are 2.15, 6.82 and 12.38, _____ would predominate at pH 5, and _____ would predominate at pH 10.

Accepted Answer

At pH 5, which is between the first and second pK values, H₂PO₄^- predominates. At pH 10, which is between the second and third pK values, HPO₄^2- predominates.

Question 5

What is the conjugate acid of H₂PO₄^-?

Accepted Answer

The conjugate acid of a base is formed by adding a proton (H+) to the base. In this case, adding H+ to HS^1- results in H2S, which is represented in the given notation as H₃PO₄.

Question 6

Which of the following shows the buffer that is found in the bloodstream?

Accepted Answer

The bicarbonate buffer system, involving H₂CO₃ and HCO₃^-, is the primary buffer system in the bloodstream.

Question 7

If a phosphate buffer (pK = 6.82) was formulated such that its pH was 7.3, it would be best suited to buffer against _____. If instead, it was formulated such that its pH was 6.3, it would be best suited to buffer against _____.

Accepted Answer

Buffers are most effective when the pH is close to the pKa of the buffering agent. A buffer with a pH above its pKa (7.3 vs. 6.82) is best suited to buffer against added acid, as it can donate protons. Conversely, a buffer with a pH below its pKa (6.3 vs. 6.82) is better at buffering against added base, as it can accept protons.

Question 8

Metabolic acidosis often causes increased respiratory rates. What portion of the bloodstream buffer is lost through increased respiration?

Accepted Answer

In metabolic acidosis, the body compensates by increasing respiration to expel more CO2, which is part of the carbonic acid (H2CO3) equilibrium, thus reducing acidity.

Quiz 1: The Chemical Foundations of Biochemistry

Which of the following would be the strongest acid?

What is the pH of a solution that contains three parts acetic acid and one part sodium acetate? The pK for acetic acid is 4.76.

If the pK values for phosphoric acid are 2.15, 6.82, and 12.38, at what pH would one observe equal amounts of H₂PO₄^- and HPO₄^2-?

If the pK values for phosphoric acid are 2.15, 6.82 and 12.38, _ would predominate at pH 5, and _ would predominate at pH 10.

What is the conjugate acid of H₂PO₄^-?

Which of the following shows the buffer that is found in the bloodstream?

If a phosphate buffer (pK = 6.82) was formulated such that its pH was 7.3, it would be best suited to buffer against _. If instead, it was formulated such that its pH was 6.3, it would be best suited to buffer against _.

Metabolic acidosis often causes increased respiratory rates. What portion of the bloodstream buffer is lost through increased respiration?

Quiz 1: The Chemical Foundations of Biochemistry

Which of the following would be the strongest acid?

What is the pH of a solution that contains three parts acetic acid and one part sodium acetate? The pK for acetic acid is 4.76.

If the pK values for phosphoric acid are 2.15, 6.82, and 12.38, at what pH would one observe equal amounts of H2PO4- and HPO42-?

If the pK values for phosphoric acid are 2.15, 6.82 and 12.38, _____ would predominate at pH 5, and _____ would predominate at pH 10.

What is the conjugate acid of H2PO4-?

Which of the following shows the buffer that is found in the bloodstream?

If a phosphate buffer (pK = 6.82) was formulated such that its pH was 7.3, it would be best suited to buffer against _____. If instead, it was formulated such that its pH was 6.3, it would be best suited to buffer against _____.

Metabolic acidosis often causes increased respiratory rates. What portion of the bloodstream buffer is lost through increased respiration?

If the pK values for phosphoric acid are 2.15, 6.82, and 12.38, at what pH would one observe equal amounts of H₂PO₄^- and HPO₄^2-?

If the pK values for phosphoric acid are 2.15, 6.82 and 12.38, _ would predominate at pH 5, and _ would predominate at pH 10.

What is the conjugate acid of H₂PO₄^-?

If a phosphate buffer (pK = 6.82) was formulated such that its pH was 7.3, it would be best suited to buffer against _. If instead, it was formulated such that its pH was 6.3, it would be best suited to buffer against _.