Radioactivity

Question 1

The radiation that will be stopped by a layer of skin/ sheet of paper is

Answer 1

Alpha radiation

Question 2

____ and ____ radiation can pass through sheets of paper but only ___ can pass through a few mm of aluminium.

Answer 2

Beta
Gamma
Gamma

Question 3

The radiation that will be stopped by a thin layer of aluminium is

Answer 3

Beta

Question 4

In a nuclear power station energy is released from changes in the _____ of the atoms of the nuclear fuel (uranium)

Answer 4

Nucleus

Question 5

Adding electrons to an uncharged atom makes it

Answer 5

A negative ion

Question 6

If a ____ source is placed inside a patient for medical reasons most of the radiation emitted will pass through the body

Answer 6

Gamma

Question 7

Removing electrons from an uncharged atom makes it

Answer 7

A positive ion

Question 8

The used fuel from a nuclear reactor is ____ and radioactive when it is removed from the reactor. After it has cooled, it has to be stored in ____ containers for ____ years because it contains radioactive isotopes with ____ half lives.

Answer 8

Hot
Sealed
Many
Very long

Question 9

An alpha particle is emitted by an unstable nucleus that has ____ protons and neutrons. The nucleus ____ 2 protons and 2 neutrons when the alpha particle is emitted.

Answer 9

Too many

Loses

Question 10

Measurements from alpha scattering experiments prove that an atom has a small ____ charged nucleus where most of the ____ of the atom is located.

Answer 10

Positively

Mass

Question 11

How is the chain reaction in a nuclear reactor controlled?

Answer 11

By the moderator made of graphite, and also by raising and lowering the control rods.

Question 12

Alpha radiation causes the most damage for every mm it passes through cells. Why is alpha radiation relatively safe as long as the source is outside your body? What if it is inside your body?

Answer 12

Alpha radiation is absorbed by the dead skin cells of your outer skin layer. If ingested, it would definitely be absorbed by your body, causing damage.

Question 13

Alpha is least penetrating because it is ____ and _____.

Answer 13

Heavier and slower

Question 14

The most penetrating is

Answer 14

Gamma

Question 15

Alpha radiation is one form of ionising radiation. What are the other two main types?

Answer 15

Beta and Gamma

Question 16

A proton has a ____ charge. An electron has an equal ____ charge. Neutrons are ____.

Answer 16

Positive
Negative
Neutral

Question 17

Isotopes are atoms of the same element with different numbers of

Answer 17

Neutrons

Question 18

How is the energy released in the nuclear reactor made to drive a turbine?

Answer 18

The energy released in a nuclear reactor heats up the coolant, which heats water and evaporates it into steam. The steam then turns the turbine.

Question 19

The protons and neutrons make up the ____ of the atom. ____ move about in the space round the nucleus. An uncharged atom has equal numbers of ___ and ____.

Answer 19

Nucleus
Electrons
Protons and Electrons

Question 20

Atoms of the same element have the same number of _____.

Answer 20

Protons

Question 21

The least penetrating radiation is

Answer 21

Alpha

Question 22

The most penetrating radiation is

Answer 22

Gamma

Question 23

The radiation with the shortest range in air

Answer 23

Alpha

Question 24

An alpha particle consists of _____ protons and _____ neutrons.

Answer 24

Two

Two

Question 25

The unit radioactivity is measured in is

Answer 25

Becquerel, or counts per minute

Question 26

A beta particle is a fast moving ____.

Answer 26

Electron

Question 27

What would this become if it emitted a beta particle?
238 /\ /
93 / \/ p

Answer 27

238 P
94 | U
Plutonium

Question 28

What would this become if it emitted an alpha particle?
238 /\ /
93 / \/ p

Answer 28

236 P
91 | A
Protactinium

Question 29

Who did an experiment with alpha particles and gold leaf?

Answer 29

Geiger and Marsden

Question 30

If 1/64th of a sample is still radioactive, how many half lives have passed?

Answer 30

Six

Question 31

How could you detect ionising radiations?

Answer 31

Geiger-Muller counter
or
Photographic film

Question 32

How much of a sample is left if 9 half lives have passed?

Answer 32

1/512th

Question 33

Describe how an ionising radiation monitoring badge works

Answer 33

The photographic film at the back is exposed by ionising radiation. One area is covered by card and aluminium and so only detects Gamma, one area is covered by card and detects Beta and Gamma and the third area detects all three.

Question 34

If 1/32th of a radioisotope is left, and 35 hours have passed, how many half lives have passed? How long is one half life?

Answer 34

5 half lives

7 hours

Question 35

Which is the nucleon number?
238 /\ /
93 / \/ p

Answer 35

238

Question 36

What are the dangers of using ionising radiation?

Answer 36

• Cause mutations, including cancers

- Can damage cells and tissue, serious exposure can give radiation sickness

Question 37

What is the atomic number?
238 /\ /
93 / \/ p

Answer 37

93

Question 38

In the Geiger Marsden experiment, what factors affect the deflection of the alpha particles?

Answer 38

Charge and speed

Question 39

What is half life?

Answer 39

The time it takes for the level of radioactivity to halve

Question 40

What are the main sources of background radiation?

Answer 40

Radon gas, rocks and buildings, food and drink, cosmic rays, medical equipment

Question 41

List some safety precautions that can be taken when using ionising radiation

Answer 41

• Reduce exposure
• ALARA- keep your dose As Low As Reasonably Achievable
• Lead shielding- lead glass, lead walls, lead aprons
• Monitor exposure

Question 42

If a half life is 3 days and there is 1/1024th left, how much time has passed?

Answer 42

30 days

Question 43

What is nuclear fission?

Answer 43

Nuclear fission is when the nuclei of Uranium are split by neutrons and releases energy.