Theory:

Chemical changes are also known as chemical reactions because they occur when one or more substances (reactants) react to create new substances (products).
 
0z4p_mvvb_210119_ss4mp_generated.jpg
 
\(A + B\rightarrow AB\)
\(Reactants\rightarrow Products\)
Here in the above chemical reaction, \(A\), \(B\) are the reactants and \(AB\) is the product.
In a community, people live in a variety of unequal circumstances. Similarly, not all the chemical reaction occurs in every circumstance. Certain conditions are necessary for any chemical reaction to take place.
 
Here are the conditions that are necessary to carry out the chemical reactions:
  
BeFunky-collage.jpg
  • Physical contact
  • Solution of reactants
  • Electricity
  • Heat
  • Light
  • Catalyst
In the upcoming sections, let us look into these conditions in brief.
Reference:
https://www.vecteezy.com/free-vector/cartoon">Cartoon Vectors by Vecteezy</a>