7 RADIOACTIVITY + PARTICLES

Question 1

Unit for radioactivity

Answer 1

Becquerel (Bq)

Question 2

Larger number of atom

Answer 2

Mass (nucleon) number

Question 3

Larger number of an atom

Answer 3

Mass (nucleon) number

Question 4

Smaller number of an atom

Answer 4

Atomic (proton) number

Question 5

Where does radiation come from

Answer 5

Emitted randomly from an unstable nucleus

Question 6

Nature of alpha

Answer 6

Helium nucleus

Question 7

Nature of beta

Answer 7

Fast-moving electron

Question 8

Nature of gamma

Answer 8

Very high frequency electromagnetic wave

Question 9

Mass of alpha

Answer 9

4

Question 10

Mass of electron

Answer 10

1/1840

Question 11

Mass of gamma

Answer 11

0

Question 12

Charge of alpha

Answer 12

2+

Question 13

Charge of beta

Answer 13

1-

Question 14

Charge of gamma

Answer 14

0

Question 15

Penetrating power of alpha

Answer 15

Low

Question 16

Penetrating power of beta

Answer 16

Medium

Question 17

Penetrating power of gamma

Answer 17

High

Question 18

Ionising power of alpha

Answer 18

High

Question 19

Ionising power of beta

Answer 19

Medium

Question 20

Ionising power of gamma

Answer 20

Low

Question 21

What stops alpha

Answer 21

Paper and thin aluminium

Question 22

What stops beta

Answer 22

Aluminium

Question 23

What stops gamma

Answer 23

Lead and concrete

Question 24

What is contamination

Answer 24

When radioisotopes get inside an object, making the object itself radioactive

Question 25

What is irradiation

Answer 25

When radiation passes through an object causing damage due to ionisation, but not leaving the object itself radioactive

Question 26

Effect on mass number of new nucleus from alpha release

Answer 26

-4

Question 27

Effect on mass number of new nucleus from beta release

Answer 27

0

Question 28

Effect on mass number of new nucleus from gamma release

Answer 28

0

Question 29

Effect on mass number of new nucleus from positron release

Answer 29

0

Question 30

Effect on atomic number of new nucleus from alpha release

Answer 30

-2

Question 31

Effect on atomic number of new nucleus from beta release

Answer 31

1+

Question 32

Effect on atomic number of new nucleus from gamma release

Answer 32

0

Question 33

Effect on atomic number of new nucleus from positron release

Answer 33

1-

Question 34

Define half-life

Answer 34

The time taken for half the radioactive nuclei to decay

Question 35

What can detect ionising radiation

Answer 35

A geiger-muller detector, OR a photographic film

Question 36

Where does background radiation come from

Answer 36

* Cosmic rays * Rocks * Medical equipment (x-rays)

Question 37

Uses of radiation

Answer 37

* Medical tracers * Sterilising food/equipment * Thickness control * Smoke detectors

Question 38

Dangers of radiation

Answer 38

* Cause mutations in living organisms * Cause cell + tissue damage * Cause skin burns

Question 39

How do you dispose of radioactive waste

Answer 39

* Bury deep in concrete * Bury in ocean * Bury deep in earth

Question 40

How do you dispose of radioactive waste

Answer 40

* Bury deep in concrete * Bury in ocean * Bury deep in earth

Question 41

Describe how power is generated in a nuclear power station

Answer 41

U-235 is bombared with slow-moving neutrons to split the nucleus into 2 daughter nuceli and some neutrons

Question 42

Function of control rods

Answer 42

Absorb extra neutrons to prevent a chain reaction

Question 43

Function of moderator

Answer 43

Slow neutrons to ensure they split nuclei

Question 44

Function of sheilding

Answer 44

Keeps radiation inside - protection

Question 45

What does a star get it's energy source from

Answer 45

Nucluer fusion

Question 46

Nature of fusion

Answer 46

Joining of 2 light helium nuclei

Question 47

Nature of fission

Answer 47

Splitting of a heavy U-235 nucleus

Question 48

Condition for fission

Answer 48

Neutron must be moderated to a slower speed

Question 49

Condition for fission

Answer 49

Neutron must be moderated to a slower speed

Question 50

Why can fusion only occur at high pressures and temperatures

Answer 50

As it needs to overcome the electrostatic repulsion force between protons

Question 51

Disadvantage of fission

Answer 51

Produces radioactive waste

Question 52

End product of fission

Answer 52

2 daughter nuclei and some neutrons

Question 53

End product of fusion

Answer 53

A helium nucleus

Question 54

How does a chain reaction occur

Answer 54

Neutrons produced by one fission split other U-235 nuclei