buffer

Definition

A buffer is a solution that resists changes in pH when small amounts of acid or base are added.

The pH of a solution is a measure of how acidic or basic it is. A pH of 7 is neutral, a pH below 7 is acidic, and a pH above 7 is basic. Buffers work by absorbing acids or bases. When an acid is added to a buffer, the buffer will react with the acid and release a base. This will help to keep the pH of the solution from changing too much. When a base is added to a buffer, the buffer will react with the base and release an acid. This will also help to keep the pH of the solution from changing too much.

Buffers are important in many different applications. They are used in laboratories to keep the pH of solutions constant during experiments. They are also used in industry to keep the pH of solutions constant in products such as shampoo and soap.

Here is an example of how a buffer works:

Imagine you have a solution with a pH of 7. This is a neutral solution, which means it is neither acidic nor basic.
Now, you add some acid to the solution. The acid will lower the pH of the solution.
However, if the solution contains a buffer, the buffer will react with the acid and release a base. This will help to keep the pH of the solution from changing too much.
As a result, the pH of the solution will not change as much as it would have if the solution did not contain a buffer.
Buffers are a valuable tool in science and industry. They help to keep the pH of solutions constant, which is important for many different applications.

Here are some of the most common buffers:

Acetic acid/sodium acetate: This is a buffer that is often used in laboratories. It is a weak acid and its conjugate base, sodium acetate.
Acetic acid/sodium acetate buffer
Tris/HCl: This is a buffer that is often used in biochemistry. It is a weak base and its conjugate acid, hydrochloric acid.

Tris/HCl buffer

Phosphate buffer: This is a buffer that is often used in biology. It is a weak acid and its conjugate base, dihydrogen phosphate.

Phosphate buffer

Buffers are classified according to their strength. Strong buffers are able to resist changes in pH more than weak buffers.

How can the word be used?

The buffer solution prevented the pH of the solution from changing too much.

Different forms of the word

Noun: buffer.

Adjective: buffering.

Verb: to buffer.

Gerund: buffering.

Plural: buffers.

Etymology

The word "burette" comes from the French word burette, which means "small, graduated flask." The French word burette is thought to be derived from the Old French word buire, which means "earthenware jug.".

Question

What is a buffer?

AQA Science Exam Question and Answer

Question:

A buffer solution is used to maintain the pH of a solution. Explain how a buffer solution works and why it is important to maintain the pH of a solution.

Answer:

A buffer solution is a solution that resists changes in pH when small amounts of acid or base are added. It works by absorbing acids or bases. When an acid is added to a buffer solution, the buffer will react with the acid and release a base. This will help to keep the pH of the solution from changing too much. When a base is added to a buffer solution, the buffer will react with the base and release an acid. This will also help to keep the pH of the solution from changing too much.

It is important to maintain the pH of a solution for a number of reasons. First, the pH of a solution can affect the stability of the solution. If the pH of a solution is too acidic or too basic, the solution may become unstable and break down. Second, the pH of a solution can affect the activity of enzymes. Enzymes are proteins that speed up chemical reactions in the body. The activity of enzymes is affected by the pH of the solution they are in. Third, the pH of a solution can affect the solubility of substances. The solubility of a substance is the amount of a substance that can dissolve in a given amount of solvent. The solubility of a substance is affected by the pH of the solution.

In conclusion, buffer solutions are important because they help to maintain the pH of a solution. The pH of a solution is important for a number of reasons, including the stability of the solution, the activity of enzymes, and the solubility of substances.