International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

In terms of particle collision theory, how does an increase in temperature affect collision outcomes?

1. Collisions become less energetic

2. It allows for a greater chance of successful collisions

3. Collisions become infrequent

4. It makes collisions ineffective

The correct answer is: It allows for a greater chance of successful collisions

An increase in temperature directly influences the kinetic energy of particles in a reaction. As temperature rises, particles move faster because they possess more energy. This increased movement leads to more frequent collisions between particles. Moreover, higher energy levels mean that a greater proportion of these collisions have sufficient energy to overcome the activation energy barrier necessary for the reaction to occur. The activation energy is the minimum energy required for a reaction to take place when particles collide. Therefore, the increase in temperature enhances the likelihood of successful collisions resulting in a reaction, making the overall collision outcomes more favorable. In summary, raising the temperature boosts both the frequency and energy of collisions, leading to a greater chance of successful interactions between reactants.