Year 10 Science · Unit 2 · Lesson 25

Using Radioisotopes, Medicine, Industry and the Environment

Challenge Worksheet

Name

Date

Class

Learning Goals

Identify and correct five misconceptions about how radioisotopes are used.
Explain the correct science behind each application and safety choice.
Demonstrate deeper reasoning by matching isotope properties to a new task.

Go Deeper

Find the mistakes

A student wrote these five statements in their revision notes

"A good medical tracer should have a long half-life so it keeps working inside the patient for many years."
"Alpha emitters are the best choice for scanning inside the body because alpha particles travel a long way and pass straight through tissue."
"Thickness gauges in factories use gamma sources because gamma rays are completely absorbed by a thin sheet of paper."
"Carbon-14 dating can be used to find the age of rocks and metal tools because all materials contain carbon-14."
"Sterilising equipment with radiation works by making the equipment itself radioactive, so it stays germ-free forever."

1. Correct statement 1. Explain what half-life a medical tracer should have, and why.

Challenge 1 mark

2. Correct statement 2. Explain which type of radiation is suitable for imaging inside the body, and why alpha radiation is not.

Challenge 1 mark

3. Correct statement 3. Explain what type of source a thickness gauge actually uses and how it detects a change in thickness.

Challenge 1 mark

Go Deeper (continued)

4. Correct statement 4. Explain what kind of material carbon-14 dating can be used on, and why it does not work on rocks or metal.

Challenge 2 marks

5. Correct statement 5. Explain how gamma sterilisation actually works and why it does not leave the equipment radioactive.

Challenge 2 marks

Show What You Know

1. An engineer needs a radioisotope to find a leak in a long underground water pipe. Recommend whether they should use an alpha, beta, or gamma source, and whether the half-life should be short or long. Justify each choice in two or three sentences, referring to detection and safety.

Challenge 3 marks

Wrap Up

Radioisotopes bring clear benefits but also risks. In two or three sentences, give your view on how the benefits and risks should be balanced when using them.