Atoms and radiation

Question 1

mass of a proton

Answer 1

1

Question 2

mass of a neutron

Answer 2

1

Question 3

mass of an electron

Answer 3

very small, practically 0

Question 4

What is radiation

Answer 4

Anything coming from the nucleus

Question 5

What are the 3 forms of radiation

Answer 5

Alpha, Beta and Gamma

Question 6

How is radiation measured

Answer 6

Geiger counter

Question 7

What was found from the Rutherford experiment

Answer 7

1/ Most of the atom is empty space
2/ There is a positive center to the atom
3/ The positive center is very dense

Question 8

How do they know most of the atom is empty space

Answer 8

Most alpha particles passed straight through the gold foil

Question 9

How do they know There is a positive center to the atom

Answer 9

Some alpha particles passed through but were deflected by varying amounts

Question 10

How do they know That the positive center is very dense

Answer 10

Very few came straight back

Question 11

What are two examples of radioactive elements

Answer 11

Uranium & Plutonium

Question 12

Alpha radiation is composed of what

Answer 12

a helium nucleus

Question 13

What is beta radiation

Answer 13

Electron fired from the nucleus

Question 14

What is gamma radiation

Answer 14

Electromagnetic wave

Question 15

What is the range of an alpha particle

Answer 15

Few cms

Question 16

What is the range of a beta particle

Answer 16

About a metre

Question 17

What is the range of gamma radiation

Answer 17

Potentially unlimited

Question 18

What is alpha radiation absorbed/stopped by

Answer 18

Paper / Skin

Question 19

What is beta radiation stopped by

Answer 19

few mm of aluminum

Question 20

What is gamma radiation stopped by

Answer 20

Few cms of lead / few feet of concrete

Question 21

State the order of deflection in a magnetic field, first being most deflected

Answer 21

1/ Beta
2/ Alpha
3/ Gamma

Question 22

In beta decay what happens to one neutron

Answer 22

One neutron is converted into a proton

Question 23

When noting beta radiation, what is wrote where the proton number is

Answer 23

The charge (which in an electron is -1)

Question 24

What measurement can you make in radioactive substances

Answer 24

The amount of time it takes for the number of radioactive nuclei to go down by a half (half life)

Question 25

What measurement cant you make in radioactive substances

Answer 25

Which nuclei will be emitted next

Question 26

What is the most ionising radiation

Answer 26

Alpha

Question 27

How does alpha ionise

Answer 27

They knock electrons away to make the atom positive

Question 28

Why is beta radiation less powerful at ionising than alpha radiation

Answer 28

Because beta radiation is much much smaller, and therefore less likely to hit

Question 29

Why is beta radiation more likely to ionise atoms

Answer 29

Have a much further range and therefore chances are increased

Question 30

Why is gamma the least likely

Answer 30

Because its simply an energy wave

Question 31

Why arent alpha radiation particles a problem outside the body

Answer 31

They cannot get it

Question 32

Why are alpha particles dangerous inside the body

Answer 32

They have lots of ionising power

Question 33

What are the uses of gamma radiation ( 3 )

Answer 33

1/ Sterilisation 2/ Kill cancer cells (radiotherapy) 3/ Tracers

Question 34

What are the uses of alpha radiation ( 2 )

Answer 34

1/ Controlling paper thickness | 2/ Smoke alarms

Question 35

What are the uses of beta radiation ( 1 )

Answer 35

1/ Controlling foil thickness

Question 36

What are the uses of general radiation ( 1 )

Answer 36

Radioactive dating

Question 37

How is it made sure paper is the correct thickness

Answer 37

Firing alpha particles at the paper

Question 38

How do we know paper is the correct thickness

Answer 38

A few particles get through

Question 39

Why is it important tracers have short lives

Answer 39

Because we want it in the body for as short as possible