The minimum amount of energy necessary to start a chemical reaction is enthalpy entropy activation energy kinetic energy

 activation energy

Explanation:

Enthalpy of the reaction is defined as the heat change in the reaction. The total energy is absorbed in the form of heat and for the reaction comes out to be positive.

Entropy is the measure of randomness or disorder of a system. If a system moves from  an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.

Activation energy is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.

Kinetic energy is the energy possessed by a body by virtue of its motion.

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