1. Unit 2 topic 5 - Rates of chemical change lesson 5
Surface area
Unit 2 topic 5 - Rates of chemical change lesson 5

2. Lesson objectives:
To understand how surface area affects the rate of reaction.
To explain how surface area affects rate using particle theory

3. Practical

4. Can you explain what you have found out from the experiment?
What did you find out?
Why did it happen?
Can you explain using particle theory?

5. Changing the Surface Area of a Solid
Large piece
Work out the surface area and volume for both
2cm
2 cm
What do you notice about the volume and surface area of each?
Broken into smaller pieces

6. Conclusion
Write a conclusion to describe what you found out.
You must link the size of the particles with surface area and the number of collisions that take place.
Which one was the fastest and why?
It is all about how many collisions there are every second.

7. Questions
Every answer should include -
the difference in the size of particles
the difference in surface area
the difference in the number of collisions per second
the difference in the rate of the reaction

8. Design a question and give it to a peer to answer.
Questions
Explain the following in detail:
Magnesium ribbon burns quickly in air but magnesium powder burns so fast that it is used in pantomimes to give the explosive flash when the genie appears.
A piece of iron bar will not burn, even in a roaring Bunsen flame but tiny iron filings are used in sparklers. It is these tiny bits of iron burning that give the orange glow.
Design a question and give it to a peer to answer.