Explaining what's happening

2 marks · Normal

State the two conditions that must be met for a collision between reactant particles to lead to a reaction, according to collision theory.

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

Also accept: Particles must collide with enough energy and with correct orientation

Common mistakes: Only mentioning energy; Mentioning only 'collide'

Show mark scheme and worked solution

Marking points

B1 · 1 mark · States particles must collide with energy equal to or greater than the activation energy

B2 · 1 mark · States that particles must collide (with correct orientation is also accepted but not required here)

Worked solution

1. The particles must collide with each other. 2. The collision must have energy equal to or greater than the activation energy.