Question

What exactly does the collision theory state?

Answer 1

Collision theory is the theory of chemical reactions. In this theory the reactant molecules collide with each other to form the products. This theory explains that in order to form a product, the reactants must collide in a particular effective way. The activation energy and the orientation of reactants affects the collision and product formation.

Complete answer:
Collision theory is a theory based on how the chemical reactions happen. According to this theory, the reactants are considered as hard spheres that collide with each other to form various products. This theory states that reactions with sufficient energy at a certain speed, collide with each other and the reaction occurs to form the products. The number of collisions per unit volume per second made by the reactants is called the collision frequency.
Various factors affect the collision theory, some are:
-Only effective collision leads to formation of products.
- The molecules should have minimum energy called threshold energy for an effective collision.
- They should have proper orientation and activation energy.
-High temperature enables the particles with more energy that make them move faster for the reaction to occur.
-Also the increased concentration of reactants, increases the chances for the reactants to collide and form products.
-For gases, an increased pressure makes the particles come closer, that enables the probability of the reaction.
Hence, collision theory states that reactants are a form of particles that collide with each other at a threshold frequency to form products.

Note:
The rate of the reaction can be determined with the collision frequency as, rate = $Z{{e}^{{}^{-{{E}_{a}}}/{}_{RT}}}$ , where Z is collision frequency. This equation when modified, is able to determine the probability of the reaction as, rate = $PZ{{e}^{{}^{-{{E}_{a}}}/{}_{RT}}}$, where P is probability factor or steric factor. By increasing the temperature, the rate constant increases.