Higher Chemistry Unit 1(a) Collision Theory and Particle Size

After today’s lesson you should be able to: explain, using collision theory, why decreasing the particle size of a solid increases reaction rate.

Small and large particles Draw two beakers and label one ‘small particles’ and one ‘large particles’. Using a coloured pencil, show how the particles of the same mass of magnesium oxide would differ in each beaker. Now add the same concentration and volume of acid – showing the arrangement of particles of the acid in each beaker (for this exercise ignore the water particles).

Looking at your diagrams: 1.Explain the relationship between particle size and surface area in each beaker. 2.Using collision theory, why is the reaction faster with smaller particles?

SCHOLAR - Higher Chemistry : Collisions and particle size SCHOLAR - Higher Chemistry : Collisions and particle size