Learn the toughest concepts covered in your GOB - General, Organic, and Biological Chemistry class with step-by-step video tutorials and practice problems.

Acids and Bases

1

Henderson-Hasselbalch Equation Concept 1

1m

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2

Henderson-Hasselbalch Equation Example 1

2m

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3

Problem

Calculate the pH of a solution formed by mixing 200 mL of a 0.400 M C_{2}H_{5}NH_{2} solution with 350 mL of a 0.450 M C_{2}H_{5}NH_{3}^{+ }solution. (K_{b} of C_{2}H_{5}NH_{2 }is 5.6 x 10 ^{-4}).

A

3.55

B

10.45

C

2.96

D

11.04

4

Henderson-Hasselbalch Equation Example 2

3m

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5

Henderson-Hasselbalch Equation Example 3

2m

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6

Problem

Determine how many grams of sodium acetate, NaCH_{3}CO_{2} (MW:82.05 g/mol), you would mix into enough 0.065 M acetic acid CH_{3}CO_{2}H (MW:60.05 g/mol) to prepare 3.2 L of a buffer with a pH of 4.58. The K_{a} is 1.8 x 10** ^{-5}**.

A

10.90 grams

B

11.68 grams

C

6.35 grams

D

2.21 grams

7

Henderson-Hasselbalch Equation Example 4

2m

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8

Problem

A buffer solution is made by combining a weak acid with its conjugate salt. What will happen to the pH if the solution is diluted to one-fourth of its original concentration?

A

The pH will increase.

B

The pH will decrease.

C

The pH will remain constant.

D

The solution will become more neutral.