The difference between replacement and shooting

"Displacement" is one of the basic types of chemical reactions. That is, a simple substance reacts with a compound to generate another simple substance and compound. Such as: mg+2hc 1 → H2+mgc 12. Belonging to redox reaction.

That is to say, the compounds involved in the reaction ionize and dissociate in the aqueous solution to form freely moving ions, which recombine into new compounds, so the reaction between acid, alkali and salt solution is generally a metathesis reaction. The metathesis reaction is the recombination of ions or ionic groups, because the valence of each element has not changed before and after this reaction, so the metathesis reaction is not a redox reaction.

Abbreviation: AB+CD=AD+CB: In aqueous solution (also called ionization), two compounds exchange elements or ions to form different compounds. That is, two compounds exchange components with each other to form two other compounds.

The essence of the metathesis reaction is that the ions in the solution combine into substances that are difficult to ionize (such as water), insoluble substances or volatile gases, so that the metathesis reaction tends to be completed. The reaction between acid, alkali and salt solution is generally formed by the exchange of components between two compounds.