Normal salt definition: a salt that contains neither ionizable hydrogen ions nor hydroxide ions.

Normal salt is a salt formed by the complete neutralization of acid and alkali. There will be no hydrogen ions in the acid or hydroxide ions in the alkali, only metal cations and acid ions. Salt. Salts in chemistry are divided into single salts and complex salts. Single salts are divided into normal salts, acid salts, and basic salts. Combined salts are divided into compound salts and complex salts.

Properties

Normal salt is the product of complete neutralization of acid and alkali, but the aqueous solution of normal salt is not necessarily neutral, such as Na2CO3 (sodium carbonate) solution is alkaline, ( NH4)2SO4 (ammonium sulfate) solution is acidic.

In the salt formed by the complete neutralization of acid and base, there will be no hydrogen ions in the acid or hydroxide ions in the base, only metal cations and acid ions. Such a salt is Right salt. Reaction to generate normal salt, such as:

HCl+NaOH=NaCl+H2O

H2SO4+Cu(OH)2 = CuSO4+2H2O

H2SO4+2NaOH =Na2SO4+2H2O, etc.

Extended information:

Normal salt is a salt formed by complete neutralization of acid and alkali. There will be no hydrogen ions in the acid, and there will be no The hydroxide ions in bases are only salts of metal cations and acid ions. Salts in chemistry are divided into single salts and complex salts. Single salts are divided into normal salts, acid salts, and basic salts. Combined salts are divided into compound salts and complex salts.

Classification of normal salts

1. Strong acid and strong alkali salts

Do not hydrolyze, because the anions and cations they ionize cannot destroy the ionization balance of water, so Neutral.

2. Strong acid and weak base salt

We call the weak base part weak yang. Weak base ions can hold the hydroxide ions ionized from the water, destroying the ionization of the water. Equilibrium causes the ionization of water to move forward. As a result, the concentration of hydrogen ions in the solution is greater than the concentration of hydroxide ions, making the aqueous solution acidic.

3. Strong base and weak acid salt

We call the weak acid part weak yin. In the same way, weak yin controls the hydrogen ions ionized from the water, making the hydroxide ions in the solution The concentration is greater than the hydrogen ion concentration, making the solution alkaline.

4. Weak acid and weak base salt

The weak acid part controls hydrogen, and the weak base part controls hydroxide, forming two weak electrolytes, and then compare their ionization constants Ka and Kb values size (rather than size of degree of hydrolysis).

At a certain temperature, the ionization constant (also called ionization equilibrium constant) of a weak electrolyte is a fixed value. This comparison can determine the nature of the salt, which one is stronger, and the ionization The constant is the negative logarithm with base 10. The one with the smaller negative value is larger.

In a word, the reaction in which the anions and cations in the salt solution control the hydrogen ions or hydroxide ions ionized from the water to form a weak electrolyte is called hydrolysis of salts.

There is also hydrolysis in organic substances, such as the hydrolysis of esters, which is the reaction of ester and water (under the conditions of inorganic acid or alkali) to generate the corresponding carboxylic acid and alcohol, which is called ester hydrolysis. There are alkaline hydrolysis of halogenated hydrocarbons, the reaction of ethyl bromide and sodium hydroxide aqueous solution to form ethanol and sodium bromide, which is called the hydrolysis of haloalkanes, and the hydrolysis of proteins, with the final products being amino acids, etc.

Reference: Baidu Encyclopedia-Normal Salt