Radioactivity

Question 1

What is radiation from uranium like?

Answer 1

Ionising

Question 2

What are the three types of radiation?

Answer 2

Alpha, Beta and Gamma

Question 3

What are substances radioactive?

Answer 3

They have an unstable nucleus

Question 4

What does the Geiger Counter do?

Answer 4

Clicks every time a particle of radiation from a radioactive substance enters the Geiger Tube

Question 5

What does Alpha decay emit?

Answer 5

2 protons and 2 neutrons

Question 6

What does a nucleus lose during Alpha decay?

Answer 6

2 protons and 2 neutrons

Question 7

What is emitted during Beta decay?

Answer 7

An electron

Question 8

What happens in the nucleus during Beta decay?

Answer 8

A neutron turns into a proton

Question 9

Where does nuclear radiation come from?

Answer 9

The nucleus of an atom

Question 10

Why are some isotopes unstable?

Answer 10

Have too many protons or neutrons

Question 11

How do nuclei become more stable?

Answer 11

Emit radiation

Question 12

What is radioactive decay?

Answer 12

When a nucleus emits radiation to become more stable

Question 13

What is the charge of Alpha radiation?

Answer 13

Positive

Question 14

What is the charge of Beta radiation?

Answer 14

Negative

Question 15

What is the charge of Gamma radiation?

Answer 15

Neutral

Question 16

What is the atomic mass of Alpha radiation?

Answer 16

4

Question 17

What is the atomic mass of Beta radiation?

Answer 17

Almost nothing

Question 18

What is the atomic mass of Gamma radiation?

Answer 18

No mass

Question 19

What is the speed of Alpha radiation?

Answer 19

Move at relatively slow speed compared to other particles

Question 20

What is the speed of Beta radiation?

Answer 20

Quite quick compared to Alpha particle

Question 21

What is the speed of Gamma radiation?

Answer 21

Speed of light

Question 22

What is Alpha radiation stopped by?

Answer 22

Paper or skin (goes through thin mica)

Question 23

What is Beta radiation stopped by?

Answer 23

Thin aluminium (goes through mica, skin and paper)

Question 24

What is Gamma radiation stopped by?

Answer 24

Anything but lead reduces gamma waves

Question 25

What is the most ionising radiation?

Answer 25

Gamma

Question 26

What is the least ionising radiation?

Answer 26

Alpha

Question 27

What is Activity?

Answer 27

The number of nuclei decaying per second

Question 28

What is Activity measured in?

Answer 28

Becquerel (Bq)

Question 29

What is 1 Bq equivalent to?

Answer 29

1 nuclei decaying per second

Question 30

What is half life?

Answer 30

The time taken for half the radioactive nuclei to decay

Question 31

What is contamination?

Answer 31

Where a radioactive material moves from one place to another

Question 32

What damages a person’s cells?

Answer 32

Ionising radiation

Question 33

What are the types of nuclear reactions?

Answer 33

Nuclear fission and nuclear fusion

Question 34

What does fission mean?

Answer 34

Splitting apart

Question 35

What happens in a nuclear fission reaction?

Answer 35

A big nucleus splits into two smaller nuclei

Question 36

What happens in a nuclear fusion reaction?

Answer 36

Two small nuclei fuse to form one big nucleus

Question 37

What are the products of nuclear fission reactions?

Answer 37

3 neutrons and energy

Question 38

Example of nuclear fission

Answer 38

1. Neutron is absorbed by uranium nucleus 2. A large unstable nucleus is formed 3. The large nucleus splits into two smaller nuclei - krypton and barium 4. Three neutrons and energy are also released at the same time

Question 39

What are control rods?

Answer 39

Absorbs surplus neutrons to keep chain reactions under control

Question 40

What is coolant?

Answer 40

Extracts heat from reactor using a heat exchanger