【Weekly Topic】(31) June 14, 2015: What is a buffer solution? What are the categories of buffer solutions?

1. A mixed solution composed of weak acids and their salts, as well as their conjugate bases and their salts, can, to a certain extent, counteract and reduce the effect of added strong acids or strong bases on the acidity of the solution, thereby maintaining a relatively stable pH value for the solution. Such a solution is called a buffer solution. 2. Aqueous solutions composed of weak acids and their salts, weak bases and their salts, acid salts of polyweak acids, and their corresponding secondary salts.

A solution that has a buffering effect on its pH value and prevents changes in that pH is called a buffer solution. Mixed solutions of weak acids and their salts, mixed solutions of weak bases and their salts.

Adding a small amount of strong acid or strong base to a buffer solution (or the formation of a small amount of acid or base as a result of a chemical reaction in the solution), or diluting the solution, results in little change in the acidity of the solution. This property is known as buffering, and a solution that possesses this buffering capacity is called a buffer solution – that is, a solution capable of stabilizing the acidity of another solution. Commonly used ones include: 1. Weak acids and their conjugate bases, such as HAC-NaAC; 2. Weak bases and their conjugate acids: NH3-NH4Cl; 3. Amphoteric substances: such as monohydrogen phosphate disodium hydrogen phosphate.

A mixed solution composed of weak acids and their salts, as well as weak bases and their salts, can to some extent counteract and reduce the effect of added strong acids or strong bases on the acidity of the solution, thereby maintaining a relatively stable pH value for the solution. This solution is called a buffer solution. Yes: 1. Weak acids and their salts (such as HAc---NaAc). 2. Weak bases and their salts (NH3·H2O---NH4Cl). 3. The composition of aqueous solutions of acid salts of polyprotic weak acids and their corresponding secondary salts (such as NaH2PO4---Na2HPO4).

Acids commonly used as buffer solutions are those solutions composed of weak acids and their conjugate bases, which possess buffering properties. The common buffer systems used in biochemical laboratories include phosphate, citrate, carbonate, acetate, barbituric acid, Tris (tris(hydroxymethyl)aminomethane), and others. Careful selection of a buffer system is necessary in biochemical experiments or research, as sometimes the factor affecting the experimental results is not the pH value of the buffer, but rather a certain ion present in it. Buffers such as borates, citrates, phosphates, and trimethylolmethane can all cause unwanted chemical reactions. Borates: Borates form double salts with many compounds, such as sucrose. Citrate: Citrate ions easily bind with calcium, so it cannot be used in the presence of calcium ions. Phosphates: In some experiments, they act as inhibitors of enzymes or even as metabolites; heavy metals tend to precipitate from solutions in the form of phosphates. Moreover, its buffering capacity is very low at pH above 7.5. Trimethylolamine: It can act together with heavy metals, but it also has an inhibitory effect in some systems. Its main drawback is the temperature effect. This aspect is often overlooked: the pH of Tris buffer is 7.8 at room temperature, 8.4 at 4°C, and 7.4 at 37°C. Therefore, when a buffer prepared at 4°C is used for measurements at 37°C, its hydrogen ion concentration increases by a factor of 10. Below pH 7.5, its buffering capacity is extremely poor.

1. A mixed solution composed of weak acids and their salts, as well as weak bases and their salts, can to some extent counteract and reduce the effect of added strong acids or strong bases on the acidity of the solution, thereby maintaining a relatively stable pH value for the solution. This solution is called a buffer solution. 2. Acids commonly used as buffer solutions are those solutions composed of weak acids and their conjugate bases, which possess buffering properties. The common buffer systems used in biochemical laboratories include phosphate, citrate, carbonate, acetate, barbituric acid, Tris (tris(hydroxymethyl)aminomethane), and others. Careful selection of a buffer system is necessary in biochemical experiments or research, as sometimes the factor affecting the experimental results is not the pH value of the buffer, but rather a certain ion present in it. Buffers such as borates, citrates, phosphates, and trimethylolmethane can all cause unwanted chemical reactions.

A mixed solution composed of weak acids and their salts, as well as weak bases and their salts, can to a certain extent counteract and reduce the effect of strong acids or strong bases that enter the system from the outside on the pH value of the solution, thereby maintaining a relatively stable pH value. Such a solution is known as a buffer solution. Buffer solutions generally consist of: 1. a weak acid and its salt (such as HAc---NaAc). 2. Weak bases and their salts (NH3·H2O---NH4Cl). 3. Composition of aqueous solutions of acid salts of polyprotic weak acids and their corresponding secondary salts.

1. A mixed solution composed of weak acids and their salts, as well as weak bases and their salts, can to some extent counteract and reduce the effect of added strong acids or strong bases on the acidity of the solution, thereby maintaining a relatively stable pH value for the solution. This solution is called a buffer solution. 2、 1) Weak acids and their salts (such as HAc---NaAc). 2) Weak bases and their salts (NH3·H2O---NH4Cl). 3) The composition of aqueous solutions of acid salts of polyprotic weak acids and their corresponding secondary salts (such as NaH2PO4---Na2HPO4).

A mixed solution composed of weak acids and their salts, as well as weak bases and their salts, can to some extent counteract and reduce the effect of added strong acids or strong bases on the acidity of the solution, thereby maintaining a relatively stable pH value for the solution. This solution is called a buffer solution. Commonly used ones include: 1. Weak acids and their conjugate bases, such as HAC-NaAC; 2. Weak bases and their conjugate acids: NH3-NH4Cl; 3. Amphoteric substances: such as monohydrogen phosphate disodium hydrogen phosphate.

A mixed solution composed of weak acids and their salts, as well as weak bases and their salts, can to some extent counteract and reduce the effect of added strong acids or strong bases on the acidity of the solution, thereby maintaining a relatively stable pH value for the solution. This solution is called a buffer solution. Commonly used ones include: 1. Weak acids and their conjugate bases, such as HAC-NaAC; 2. Weak bases and their conjugate acids: NH3-NH4Cl; 3. Amphoteric substances: such as monohydrogen phosphate disodium hydrogen phosphate. OP, it seems that others’ answers can be seen. .