Radio activity

Question 1

what is the definition of an isotope

Answer 1

An element with the same number of protons but different number of neutrons so the mass number is different

Question 2

Describe an Alpha Particle

Answer 2

Helium nucleus
low penetration ( stopped by paper)
Very Ionising
mass number of 4
Atomic number as 2
charge of +2
During radiation a helium nucleus is emitted from the nucleus

Question 3

Describe a Beta particle

Answer 3

In radiation an electron is emitted from the nucleus.

Moderate ionisation
Moderate Penetration (stopped by Aluminium)

Question 4

Describe a Gamma Particle

Answer 4

not very ionising
Very penetrating

Question 5

List three radioactive particles

Answer 5

Beta
Alpha
Gamma

Question 6

what is decay

Answer 6

the process of ejecting radiation

Question 7

when a nucleus is unstable what does it do

Answer 7

It tries to become more stable, by either ejecting mass or energy

Question 8

what do Becquerels measure (Bq)

Answer 8

Activity

Question 9

what is the mass number and atomic number for beta

Answer 9

mass number-0
Atomic number-+!
the atomic number gains an electron
mass number remains unchanged

Question 10

what is the mass number and atomic number for Gamma

Answer 10

mass number - 0
atomic number- 0

Question 11

what is the mass number and atomic number for Alpha

Answer 11

mass number- 4
Atomic number- 2

Question 12

what is Gamma stopped by

Answer 12

1km of air
10 cm of lead

Question 13

what is Beta stopped by

Answer 13

1m of air
3mm of Aluminium

Question 14

what is Alpha stopped by

Answer 14

3-7 cm of air
a single piece of Paper

Question 15

Name the detector used to measure the penetration of different radioactive elements

Answer 15

GM tube
Geiger Muller tube

Question 16

what are precautions used when handling radioactive elements

Answer 16

wear PPE- gloves, goggles
Use tongs- increase distance
Don’t point directly towards you
place source in a lead container
limit exposure time to radioactive element

Question 17

what is the difference between beta and alpha

Answer 17

alpha has a larger mass and a bigger charge- means it is more ionising and less penetrating

alpha is a helium Nucleus

alpha has a a charge of +2 and a mass number of 4

Question 18

Gamma is the odd one out state why

Answer 18

only element which is an electromagnetic wave

only one that doesn’t have a mass or a charge

Alpha and Beta are particles

Question 19

Name sources of background radiation

Answer 19

cosmic rays
radon gas
Food/Drink
Humans
buildings
Nuclear power
Medical (x-rays)

Question 20

Define HALF LIFE

Answer 20

the time taken for half the undecayed nuclei to decay

Question 21

name two detectors for ionising radiation

Answer 21

GM tube- Geiger Muller tube
Photographic Film

Question 22

what is meant by the term Irradiation

Answer 22

When someone is exposed to A/B/Y from a near by source

once the person moves away the irradiation stops

Question 23

what is meant by the term Contamination

Answer 23

When someone gets particles of a radioactive source on their person or inside their body

they will continue to be exposed to radiation until the material has all decayed or it is removed

Question 24

How is gamma source used to treat Cancerous tumours in the body.

Answer 24

The source is rotated around the tumour.

the gamma radiation always passes through the tumour, it receives a large does of radiation which will kill cancer cells

the gamma radiation does not pass through the same healthy tissue, it receives a lower dose, less damage

Question 25

why does the doctor stay away from the patient

Answer 25

Increasing the distance decreases the count rate/ dose that the doctor receives.

this will cause less damage to the doctors body
( Which is important as they are exposed to radiation daily)

Question 26

why is alpha not used for a radioactive tracer

Answer 26

because it is most ionising least penetrating
Alpha can be stopped by a single sheet of paper
if injected it can causes significant damage to internal organs

Question 27

What is a chain reaction

Answer 27

Neutrons released in fission can be absorbed by other nuclei

these nuclei split (fission)
fission releases more neutrons

neutrons released in fission can be absorbed by other nuclei and so on