Answer: double displacement reaction
Step-by-step explanation:
A double displacement reaction is one in which exchange of ions take place.
The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Example:
As can be seen in the chemical reaction, cations are replaced by cations and anions are replaced by anions.
Thus a reaction in which two ions switch places is double displacement reaction.