Agree Learning Outcomes: Topic: P6.2.2. Spec link: P6 Time: 70 mins Recorded Assessment: Review: Students peer mark each others cartoons Present New Knowledge: How does Nuclear Fission work? Agree Learning Outcomes: Recall the type of nuclei that may undergo nuclear fission Describe what emerges from nuclear fission Explain a chain reaction Apply To Demonstrate: Students produce a cartoon strip explaining how Nuclear Energy is produced. Construct Meaning: Experiment with PHET simulation of Nuclear Fission, exploring the role of the control rods and the chain reaction within a Nuclear reactor.

What do the following images have in common? BELL What do the following images have in common? The black and white photo is from Chernobyl in 1986

Learning outcomes Recall the type of nuclei that may undergo nuclear fission Describe what emerges from nuclear fission Explain a chain reaction

Nuclear fuel is used to boil water in a “heat exchanger” City National Grid Pylons Talk through how Electricity is generated , the same principles are true in a conventional power station. Print out this slide and the next for students to stick in books and complete the missing words/labels. Nuclear fuel is used to boil water in a “heat exchanger”

which turns water into steam. 1 kg of Nuclear fuel produces same amount of energy as 30,000 T of coal Nuclear reactions produce heat which turns water into steam. The steam then turns the turbine which turns the generator which generates electricity. Print for students to complete and stick in books

So how does a nuclear power station produce heat?

Nuclear fission More neutrons Neutron Uranium or plutonium nucleus Unstable nucleus Twist a balloon into two to demonstrate the nucleus splitting into two parts. Cut the balloon in the centre, the balloon will burst. This simulates the energy being created as the unstable nuclei split. New nuclei (e.g. barium and krypton)

Chain reactions Talk through the reaction, the new neutrons produced from each fission reaction go on to cause a new fission reaction in neighbouring Uranium nuclei, creating a chain reaction. Each fission reaction releases neutrons that are used in further reactions.

What does it look like in practice? https://phet.colorado.edu/en/simulation/nuclear-fission This PHET simulation shows the chain reaction If you raise and lower the control rods in the nuclear reactor you will see less/more neutrons. This is how Nuclear Fission is controlled Students can use this to see what happens - give them 5 minutes to explore.

How do we control Nuclear Fission Control rods are made of a material such as Boron or silver which will absorb neutrons By raising/lowering the control rods you can control how many neutrons are free.

Create a cartoon strip to show Nuclear Fission Ask students to explain Nuclear Fission through a cartoon strip, check they have included how electricity is created; the inital Nuclear fission reaction and then the chain reaction. Make sure they show that 2/3 neutrons produced from the nuclear fission reaction and they go on. They should mention the need to control the nuclear fission reaction with Boron rods in the Nuclear reactor which absorb neutrons.

Success Criteria Picture/explanation on Nuclear Fission reaction (4) Picture/explanation of the chain reaction (4) Picture/explanation of how electricity produced (4) Picture/explanation of how the control rods work (3) Correctly labelled with names of elements (3) Aesthetics (2)

What problems does it produce and how is it dealt with? Nuclear fission What is it? What does it release? What problems does it produce and how is it dealt with? What is meant by the term “chain reaction”? Carefully describe how the chain reaction controlled. p260-1 Answers on next slide...

Splitting of a large nucleus Release of large amounts of energy Radioactive waste, disposed safely A neutron cause the decay of an atom. This decay produces more neutrons that start even more decay chains… Boron control rods absorb neutrons. This slows the chain reaction p244-7 Answers on next slide...