Answer:
Step-by-step explanation:
A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution. Thus one element should be different from another element.
According to law of conservation of mass, the mass can neither be created nor be destroyed. Thus the mass of products must be equal to the mass of reactants. In order to have same mass on both sides of the chemical equation, the number of atoms of each element must be same in reactants as well as products. Thus all the chemical equations are balanced.
The balanced single displacement reaction can be represented as :