Define Chemical Reactions & Equations

Updated on Jan. 18, 2021 04:39 PM IST by Lakshmi Arya

Types of Chemical Reaction :--

Displacement Reaction:-The chemical reaction, in which more reactive element, displaces less reactive element from its salt solution. Example:- Fe(s) + CuSO4(aq)      --------->      FeSO4(aq)     +     Cu(s)   Blue colour of solution due to CuSO4 changes into light green colour, due to formation of FeSO4

Combination Reaction:- The chemical reaction, in which two or more reactant combine to give a single product. Example:- CaO(s)   +   H2O(I)   --------------->     Ca(OH)2(aq))

Decomposition Reaction:-The chemical reaction, in which single reactant decompose (breaks) into two or more products. Types of decomposition reaction:-

  1. Thermal decomposition: - When decomposition is done by heating.  FeSO4(s)    +    Heat     ———>    Fe2O3(s)    +    SO2(g)     +     SO3(g)  
  2. Electrolytic decomposition: When decomposition is done by passing electricity.  2H2O(I)   —————>  2 H2(g)   +   O2(g)
  3. Photolytic Decomposition:- When decomposition is done by light /sun light.    2AgCl ————> 2Ag + Cl2
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Related FAQs

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