Answer: The correct answer is parts of compounds switch places to form two new compounds.
Explanation:
Double displacement reaction is defined as the reaction in which exchange of ions takes place to form two different compounds.
Decomposition reaction is defined as the chemical reaction in which a larger molecule breaks down into two or more smaller molecules.
Single displacement reaction is defined as a reaction in which more reactive metal displaces a less reactive metal from its chemical reaction.
Synthesis reaction is defined as the chemical reaction in which two or more smaller molecules combine to form a single larger molecule.
Hence, the correct answer is parts of compounds switch places to form two new compounds.
