P2.5 and P2.6 Radiation

Question 1

What must always stay the same in an element?

Answer 1

The number of protons and electrons.

Question 2

What does the number of protons in a nucleus determine?

Answer 2

What element it is.

Question 3

What is an ion?

Answer 3

An atom with a charge that has lost or gained an electron.

Question 4

What is an isotope?

Answer 4

A version of an element with more neutrons than it normally has.

Question 5

What is ionising radiation?

Answer 5

Radiation that has enough power to make atoms lose electrons and become ions.

Question 6

What are the three types of radiation?

Answer 6

Alpha, Beta and Gamma

Question 7

What happens when an atom decays?

Answer 7

It emits alpha, beta and gamma radiation and becomes a smaller nucleus that is stable.

Question 8

What os the penetration order for different types of radiation?

Answer 8

Gamma, beta, alpha.

Question 9

What is the ionising order for radiation?

Answer 9

Alpha, beta, gamma.

Question 10

How can you stop the three types of radiation?

Answer 10

Alpha: Paper or skin
Beta: aluminium
Gamma: Lead

Question 11

What is nuclear fission?

Answer 11

A uranium 235 atom is split by adding another neutron. This then splits into two daughter nuclei and three more neutrons are released, as well as kinetic and thermal energy.

Question 12

What are daughter nuclei?

Answer 12

The two nuclei produced during fission.

Question 13

What are control rods in a nuclear reactors?

Answer 13

They absorb some neutrons

Question 14

What are fuel rods?

Answer 14

Rods in a nuclear reactor that contain the Uranium235 for the reactions.

Question 15

What is a moderator?

Answer 15

A material in the core that slows down the fast moving neutrons so that they are more likely to react with another Uranium atom.

Question 16

How is electricity generated in a nuclear reactor?

Answer 16

The thermal energy is used to heat up water which heats up other water to spin a turbine which produces electricity. The steam is then cooled and the heated water cooled as well.

Question 17

What is radioactive waste made of?

Answer 17

Daughter nuclei and radioactive isotopes formed in the reaction.

Question 18

What is nuclear fusion?

Answer 18

When small nuclei combine to create a bigger one.

Question 19

Where is fusion most commonly found?

Answer 19

In stars.

Question 20

What elements often combine in fusion to form what?

Answer 20

Hydrogen to form helium - Often Hydrogen2 and Hydrogen3 to make helium and an extra neutron.

Question 21

What is a common effect of too much radiation exposure?

Answer 21

Cancer.

Question 22

What can occur in cells as a result of exposure to radiation?

Answer 22

Mutations.

Question 23

What are the three stages of nuclear waste?

Answer 23

High level waste (HLW)
Intermediate level waste (ILW)
Low level waste (LLW)

Question 24

For how long does radioactive waste stay at each of the levels?

Answer 24

HLW- 50 years
ILW- >10000 years
LLW- > 10000 years

Question 25

What is the half-life of an element?

Answer 25

The time it takes for half the nuclei in a sample of it to decay.

Question 26

What can happen to an element after decaying?

Answer 26

It may become stable.

Question 27

How do you measure radioactivity?

Answer 27

With a Geiger-Müller tube.

Question 28

What is background radiation?

Answer 28

Low levels of radiation found naturally.

Question 29

What is a large contributor to background radiation?

Answer 29

Radon gas.

Question 30

What are some of the uses of radiation?

Answer 30

Diagnosis of Cancer
Treatment of Cancer
Irradiating food
Sterilising equipment
Smoke alarms
Tracers in the environment
Checking material thicknesses.