The correct sequence for product formation according to the Collision theory of chemical reaction is

(A) Proper orientation
(B) Molecules collide with threshold energy
(C) Intermediate formation
(D) Formation of products

Choose the correct answer from the options given below:

(B), (A), (C), (D)

The correct answer is Option (1) → (B), (A), (C), (D)

According to the Collision Theory of chemical reactions, for a reaction to occur and result in product formation, specific criteria must be met in a logical sequence:

(B) Molecules collide with threshold energy: First, reactant molecules must collide. However, not all collisions result in a reaction. They must possess a minimum amount of energy, known as threshold energy, to break existing bonds.

(A) Proper orientation: Even if molecules have enough energy, they must collide in the correct spatial arrangement (proper orientation) so that the reacting atoms can come into contact and form new bonds.

(C) Intermediate formation: Once an effective collision (sufficient energy + proper orientation) occurs, the system reaches a high-energy state known as the activated complex or transition state (intermediate).

(D) Formation of products: Finally, the unstable intermediate breaks down to form the stable products.