Match List I with List II

Choose the correct answer from the options given below:

(A)-(I), (B)-(II), (C)-(III), (D)-(IV)

The correct answer is option 1. (A)-(I), (B)-(II), (C)-(III), (D)-(IV).

Let us go through each term and its corresponding description:

(A) Activation energy - (I) Difference in the energy of activated complexes and reactants:

Activation energy is the minimum amount of energy required for a chemical reaction to occur. It represents the energy barrier that reactant molecules must overcome for the reaction to proceed. This energy difference between the activated complex (transition state) and the reactants is what is referred to as activation energy.

(B) Threshold energy - (II) Minimum energy possessed by reactant molecule to form effective collisions:

Threshold energy is another term for activation energy. It represents the minimum amount of energy that reactant molecules must possess to undergo effective collisions and initiate a chemical reaction.

(C) Heat of Reaction - (III) Negative for exothermic reactions:

The heat of reaction, also known as enthalpy change (\(\Delta H\)), is the amount of heat absorbed or released during a chemical reaction. For exothermic reactions, heat is released to the surroundings, resulting in a negative heat of reaction value.

(D) Role of a catalyst - (IV) To give a new path of reaction:

A catalyst is a substance that increases the rate of a chemical reaction by providing an alternative reaction pathway with a lower activation energy. It does not alter the overall energy difference between reactants and products or the equilibrium position of the reaction.

So, the correct matching is option 1. (A)-(I), (B)-(II), (C)-(III), (D)-(IV)