Question

why decomposition reaction is called opposite of combination reaction write equation plz help me fast guys ​

Answer 1

Answer:

bcoz..in combination reaction two or more substance combine to form a single substance

CaO + CO2 = CaCO3

whereas in decomposition reaction singke compound decomposes into 2 or more substance in presence of energy

H2O = H2 + O2

Answer 2

Decomposition reaction is called the opposite of combination reaction as in decomposition reaction a single substance breaks down to form two substances.

Eg.     ZnCo3         ----->      ZnO(s)     +    CO2(g)

(Zinc Carbonate)   heat   (Zinc Oxide)

Whereas in combination reaction two substances combine to form a single substance.

Eg.   Mg(s) + O2(g) ----->  MgO(s)

                                (Magnesium Oxide)