Question

Complete the following : $(CH_{3}COO)_{2}Pb + Na_{2}S \longrightarrow$

Answer 1

When two different molecules having cations and anions that change or switch places it is called double displacement reaction.

This is a kind of decomposition reaction unlike the synthesis reaction the more complex molecules break into smaller, easier or we can say simpler molecules.  

$(CH_3COO)_2Pb + Na_2S\rightarrow PbS + 2(CH_3COO)Na$

Double displacement reaction is a kind of decomposition reaction which is also called metathesis.