Section+4c

= back to IGCSE chemistry = =** Rates of reactions ** = =In this section, you will be assessed on your ability to:= 4.17 describe experiments to investigate the effects of changes in surface area of a solid, concentration of solutions, temperature and the use of a catalyst on the rate of a reaction 4.18 describe the effects of changes in surface area of a solid, concentration of solutions, pressure of gases, temperature and the use of a catalyst on the rate of a reaction 4.19 understand the term ‘activation energy’ and represent it on a reaction profile 4.20 explain the effects of changes in surface area of a solid, concentration of solutions, pressure of gases and temperature on the rate of a reaction in terms of particle collision theory 4.21 explain that a catalyst speeds up a reaction by providing an alternative pathway with lower activation energy. = Section notes = = Book = Chapter 6 pages 41 to 51 = Investigations = = Resources =

Animations
[|surface area] [|factors affecting rates] [|sodium thiosulphate reaction] Alternatively use this one on eChalk; you will need to use a username and password which you can get from me: [|rates of reactions] [|rates of reactions animation 1]

Worksheets




Images
Activation energy = Revision = Use this site to help you to revise - it also contains a few simple animations: [|sciencepages] You can also use the following two BBC bitesize ones, each from a different exam board: 1. [] 2. []
 * [[image:http://www.chem.ufl.edu/~itl/2045/matter/FG14_013.GIF width="232" height="156" caption="Activation energy can be thought of as a hill which particles need to climb before they can be changed into products"]] || [[image:http://t1.gstatic.com/images?q=tbn:ANd9GcRmgBzuTqsr8sQpEt-qeuM-4rCeOtd-82ktV8HoGv-T0SkNtjqRUg width="291" height="206" caption="Activation energy on a reaction profile or energy level diagram"]] ||