Question

give one example each of displacement, decomposition and combination reactant with explanation

Answer 1

in Displacement reaction =
Fe+cuso4 gives feso4+Cu
here iron is highly reactive then coper.

decomposition have three type
1) thermal decomposition = caco3 gives cao+ co2
2) electroloytic = h2o gives h2 +o2
3) photochemical = agcl2 gives ag + cl2

in combinations reaction= cao+h2o gives ca(oh)2

Answer 2

when two or more reactants combine in a reaction to form a single product it is called a combination reaction .

the chemical reaction in which two or more products are formed from a single reactant is called decomposition reaction .

the reaction in which the place of the iron of a less reactive element in a compound is taken by another more reactive element by formation of its own ions is called displacement reaction .

I hope this is helpful for you