Problem:

Question 1: Convert the number of drops at which the buffer stopped maintaining a nearly constant pH to the total buffering capacity.

Multiply the number of drops by the conversion factor from the Background section of your Lab Manual (0.025 mmol/drop), and divide by the total volume of buffer used (5 mL) to obtain the total buffering capacity, in mmol/mL.

For example, if the number of drops was 4, when it is multiplied by 0.025 mmol/drop the result is 0.1 mmol. That number is divided by 5, and the result is 0.2 mmol/mL.

What is the total buffer capacity for the phosphate buffer?

0.04 mmol/mL

0.2 mmol/ml

0.0013 mmol/ml

0.8 mmol/ml

Question 2: How do buffers neutralize acids and bases?

1) The buffer components bind to acids or to bases, causing them to precipit out of solution so that they can not effect the pH.

2 )The buffer's weak acid releases protons to neutralize bases, and the conjugate base absorbs protons to neutralize acids.

3)The buffer's weak acid is attracted to other acids and surrounds them so that they can not interact with the solution. The conjugate base does the same with the bases.

4)The buffer components bind to acids or to bases, forming gases that evaporate out of solution so that they cannot effect the pH.

Question 3: Why is the buffer's ability to maintain a constant pH limited to the addition of a specific amount of acid or base?

A. Once one of the buffer's components has released or absorbed all its available protons, the buffer can no longer maintain a constant pH.

B. B. Once the buffer has precipitated a large amount of acid or of base, it uses up all the empty space that can hold the solid precipitate.

C. Once a large quantity of acid or of base is added, the buffer is diluted to the point where the solution is essentially an acid or a base.

It depends on the buffer in question; higher quality buffers can neutralize larger amounts of acid or base

Question 4: What is the biological significance of buffers?

A. Buffers prevent even the slightest changes in pH that can inhibit important biological molecules such as enzymes.

B. All of the answer choices are examples of the biological significance of buffers.

C. Buffers prevent acidic or basic foods from altering the pH of the digestive system.

D. Buffers prevent stomach acids from escaping the stomach and digesting other tissues in the body.

Please provide correct answer.