A metathesis reaction, also known as a double displacement reaction, is a chemical reaction where two compounds exchange components to form two new compounds. This type of reaction often involves the swapping of ions, and it can be represented by the general equation:
A-B + C-D → A-D + C-B
In simple terms, the partners in the reactants switch places to create new products.
An example of a metathesis reaction can be seen in the reaction between sodium chloride (NaCl) and silver nitrate (AgNO3):
NaCl + AgNO3 → NaNO3 + AgCl
In this reaction, the sodium (Na+) from sodium chloride swaps places with the silver (Ag+) from silver nitrate. As a result, sodium nitrate is formed along with silver chloride, which often precipitates out of solution as a solid.