Radioactivity

Question 1

Finish the sentence

The process of an object emitting radiation is called ________

Answer 1

Radioactivity

Question 2

Finish the sentence

An object that is emitting radiation is known as ____________

Answer 2

Radioactive

Question 3

What is a half life

Answer 3

the time taken for:

• The number of nuclei( or atoms) of the radioactive isotope in a sample to halve
• The count rate from a sample containing the radioactive isotope to fall to half its starting level

Question 4

An isotope has a half life of 25 days. if you started with 2000g after 100 days how much would be left?

Answer 4

125g

Question 5

A scientist has an isotope with a half life of 3 days. After 9 days he has 30g left. How much did he start with?

Answer 5

240g

Question 6

800g of an isotope was left for 1 day (24 hours). After that time there was 50g left. What is the half life of the sample?

Answer 6

6 hours

Question 7

What changes when a radioactive substance decays

Answer 7

It gives out nuclear radiation

Question 8

List benefits of using radioactive substances in a hospital

Answer 8

Sterilising equipment and food
Radioactive tracers and X-Rays are used to investigate a patient’s body without the need for surgery
Treat cancer with gamma rays

Question 9

List risks of using radioactive substances in a hospital

Answer 9

Ionising radiation mutates cells causing damage

These mutations can lead to cancer