Radioactivity

Question 1

What was Daltons atom model and what date was it discovered?

Answer 1

Billiard ball

1805

Question 2

What was Thompson’s model of an atom and what year was it discovered?

Answer 2

Plum pudding model

1904

Question 3

What was Rutherford atom model and what year was it discovered?

Answer 3

Nuclear atomic model

1911

Question 4

How did Rutherford find out that the atom was mostly empty space?

Answer 4

He fired alpha particles at gold leaf, most of the particles went through

Question 5

What relative mass and relative charge does a proton have?

Answer 5

relative mass = 1

Relative charge = +1

Question 6

What relative mass and relative charge does a neutron have?

Answer 6

Relative mass = 1

Relative charge = 0

Question 7

What relative mass and relative charge does an electron have?

Answer 7

Relative mass = 1/2000

Relative charge = -1

Question 8

What happens if an electron absorbs radiation?

Answer 8

It moves up an energy level

Question 9

What level of energy does a shell close to the nucleus have?

Answer 9

Low energy

Question 10

What level of energy does a shell far from the nucleus have?

Answer 10

High energy

Question 11

What happens if an outer electron absorbs lots of radiation?

Answer 11

It leaves the atom, making it a free electron which has been ionised

Question 12

What does ionised mean?

Answer 12

An atom which has lost an electron

Question 13

Once the electron has left the atom, what has it become?

Answer 13

A positive ion because there are more protons than electrons

Question 14

What is alpha?

Answer 14

A helium atom

Question 15

What can alpha be absorbed by?

Answer 15

A thin sheet of paper

Question 16

What happens in alpha decay?

Answer 16

Mass number - 4

Atomic number - 2

Question 17

What can beta plus be absorbed by?

Answer 17

Aluminium

Question 18

What happens in beta plus decay?

Answer 18

Mass number doesn’t change

Atomic number +1

Question 19

What is beta minus absorbed by?

Answer 19

Aluminium

Question 20

What happens in beta minus?

Answer 20

Mass number doesn’t change

Atomic number -1

Question 21

What is gamma absorbed by?

Answer 21

Lead or concrete

Question 22

What happens in gamma decay?

Answer 22

Mass and atomic number stay the same

Question 23

What is decay?

Answer 23

The process of ejecting the radiation

Question 24

What is an isotope?

Answer 24

Atoms of the same element with different numbers of electrons

Question 25

How do you work out the number of neutrons in an atom?

Answer 25

Mass number - atomic number

Question 26

What are the 2 definitions of half life?

Answer 26

The time it takes for the activity of a sample to fall in half OR The time taken for half the radioactive nuclei to decay

Question 27

What does the Geiger muller tube do?

Answer 27

Detects when the gas inside the chamber is ionised by radiation

Question 28

What is background radiation?

Answer 28

Low level radiation that is around us all the time

Question 29

What are the 6 types of background radiation? | Most to least effective

Answer 29

``` Radon gas Medical Ground/buildings Cosmic rays Food Nuclear power ```

Question 30

What does stable mean?

Answer 30

Doesn’t decay

Question 31

What does unstable mean?

Answer 31

Does decay

Question 32

What is contamination?

Answer 32

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

Question 33

When does exposure stop for someone who is contaminated?

Answer 33

When the source has finished decaying

Question 34

What is irradiation?

Answer 34

When someone is exposed to alpha/beta/gamma from a nearby source

Question 35

When does exposure for someone with irradiation stop?

Answer 35

When they move away

Question 36

What are 2 safety items for people who are constantly exposed to radiation?

Answer 36

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