A buffer is a solution that resists changes in pH when small amounts of acid or base are added to it.
What Are the Different Types of Buffers?
There are two main types of buffers:
- Acidic buffers are designed to resist changes in pH when small amounts of base are added to them.
- Basic buffers are designed to resist changes in pH when small amounts of acid are added to them.
What Are the Applications of Buffers?
Buffers are used in a wide variety of applications, including:
- Maintaining the pH of biological systems – Buffers are used to maintain the pH of body fluids, such as blood and urine.
- Controlling the pH of chemical reactions – Buffers are used to control the pH of chemical reactions, such as those used in the production of pharmaceuticals and food.
- Calibrating pH meters – Buffers are used to calibrate pH meters, which are used to measure the pH of solutions.
How Are Buffers Prepared?
Buffers are prepared by mixing a weak acid with its conjugate base or a weak base with its conjugate acid.
Key Features of a Buffer
- Resists Changes in pH – Buffers resist changes in pH when small amounts of acid or base are added to them.
- Contains a Weak Acid and Its Conjugate Base or a Weak Base and Its Conjugate Acid – Buffers are prepared by mixing a weak acid with its conjugate base or a weak base with its conjugate acid.
- Has a pH Near the pKa of the Weak Acid or Weak Base – The pH of a buffer is near the pKa of the weak acid or weak base that is used to prepare it.
Statements That Describe a Buffer
Select the statement that best describes a buffer:
- A buffer is a solution that maintains a constant pH.
- A buffer is a solution that resists changes in pH.
- A buffer is a solution that contains a weak acid and its conjugate base.
- A buffer is a solution that contains a weak base and its conjugate acid.
Answer
The correct answer is:
- A buffer is a solution that resists changes in pH.
Additional Information
Buffers are an important part of many chemical and biological systems. They help to maintain the pH of solutions, which is critical for many processes. Buffers are also used to calibrate pH meters and to control the pH of chemical reactions.