Question

explain the following reactions with example. (i) combination reaction. (ii) double displacement reaction

Answer 1

combination reaction is when 2or more elements or compounds combine to for a single compound
eg- 2H2 +O2-------> 2H2O
C + O2------> CO2
double displacement reaction is a type of chemical reaction where two compounds react, and the positive ions (cation) and the negative ions (anion) of the two reactants switch places, forming two new compounds or products.
eg- Na2S +HCl -----> NaCl + H2S
hope it helps