L3 - Deflection of Ionising Radiation

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objectives

Describe the deflection of ɑ-particles, β-particles and 𝛄-rays i electric and magnetic fields
Use Word Equations to represent changes in the composition of the nucleus when particles are emitted
Use Nuclide Notation in equations to show ɑ and β decay

Look at this picture - what is the difference between the two nuclei? What kind of radiation was emitted and how do you know?

When a Nuclei undergoes ALPHA DECAY the ELEMENT CHANGES AS THE PROTON NUMBER DECREASES BY 2 and the MASS NUMBER DECREASES BY 4

Complete Word and Nuclide Notation Alpha Decay Equations for:

When a Nuclei undergoes BETA DECAY the ELEMENT CHANGES AS THE PROTON NUMBER INCREASES BY 1 and the MASS NUMBER STAYS THE SAME

Complete Word and Nuclide Notation Beta Decay Equations for:

Write 3 Paragraphs - one for how each type of radiation is deflected

Use the PEEL Framework

Explain what the picture shows you

How does Ionising Radiation deflect through a Magnetic Field?

As deflection is caused by ratio of mass to charge you can observe:

Alpha particles deflect in one direction - but not by much as they have the largest mass
Beta particles deflect in the opposite direction to alpha as they have a negative charge - they are lighter so deflect more
Gamma radiation does not deflect as it does not have a charge

J J Thompson

Discovered the Electron!

Proposed the ‘Plum Pudding Model’ where electrons are surrounded by a soup (or cloud) of positive charges

Stated that electrons were in fixed positions within the atom See below picture:

Follow this Link and complete the following activities:

First Play the experiment using Thomspon’s Plum Pudding Model - What would Rutherford hypothesise if Thompson’s model was correct?
What actually happened when Rutherford Fired ɑ-particles at the gold foil?
What Observations can you make when you fire the ɑ-particles by adjusting the variables?