What is the cation and anion of K2 S?

Answer : Graph 1 is an endothermic reaction and Graph 2 is an exothermic reaction. The labeling of both the graphs are shown below.

Explanation :

Endothermic reaction : In this reaction, the energy is absorbed from the surrounding.

In the endothermic reaction, the energy of reactant are less than the energy of product.

Exothermic reaction : In this reaction, the energy is released into the surrounding.

In the exothermic reaction, the energy of reactant are more than the energy of product.

Transition state : It is a state when the reactant molecules absorb energy then their bonds are loosened and new lose bonds are formed between them. The intermediate formed is known as activated complex or transition state. It is unstable state and immediately dissociates to form the stable products.

Activation energy : The minimum amount of energy absorbed by the reactant molecules so that their energy becomes equal to the threshold energy.

Hence, the labeling of both the graph 1 and 2 are shown below.