Atoms And Radiation

Question 1

Radioactive decay

Answer 1

• spontaneous and random

- can’t predict when or if a particle decays

Question 2

Half life

Answer 2

Time taken for half of the nuclei to decay

Question 3

Long half life

Answer 3

Less radiation for a very long time
Less dangerous immediately
Radiation is spread out
Stays dangerous for long

Question 4

Short half life

Answer 4

Lots of radiation quickly
Immediately dangerous
Becomes safe after a short period of time
All of it comes out in a short period of time

Question 5

Bq

Answer 5

Unit of activity

Becquerels

Question 6

Proton

Answer 6

A positive particle in the nucleus

One of two nucleons

Question 7

Neutron

Answer 7

A neutral particle in the nucleus

One of two nucleons

Question 8

Nucleon

Answer 8

Total number of protons and neutrons in the nucleus of an atom
They’re both roughly the same size and account for most of the mass of the atom

Question 9

Nucleus

Answer 9

The centre of the atom
You
Made up of positive protons and neutral neutrons

Nearly all of the mass of the atom is in the nucleus

Question 10

Nuclide

Answer 10

A specific arrangement of protons and neutrons in a nucleus

Question 11

Isotope

Answer 11

Two versions of an atom with the same number of protons and different number of neutrons

Question 12

Random

Answer 12

Can’t be predicted

Question 13

Spontaneous

Answer 13

Not caused by anything

Question 14

Decay

Answer 14

When an unstable nucleus turns into a more stable nucleus (emits radiation)

Question 15

Activity

Answer 15

Number of decay in a second

Question 16

How do electrons absorb and emit radiation?

Answer 16

Based on the energy levels they move between

Question 17

Different energy =

Answer 17

Different wavelengths

Question 18

Ionisation

Answer 18

If electrons in an atom absorb nuclear radiation (alpha, beta or gamma) an electron can be completely removed

Removing an electron from an atom to create an ion

Question 19

What can cause mutation?

Answer 19

If atoms inside a living cell’s DNA become ionised

Can lead to death, birth defects or cancer

Question 20

Energy level

Answer 20

‘Shells’ inside an atom

Question 21

Frequency

Answer 21

Number of complete waves every second

Question 22

Mutation

Answer 22

Changing the DNA of a cell

Question 23

Contamination

Answer 23

Radioactive mason or in something, which makes it radioactive

Question 24

Irradiation

Answer 24

Putting radiation on something

Question 25

Radioactive tracer

Answer 25

A radioactive isotope that you inject or feed into a living person to see where a person is

Question 26

Why do nuclear weapons: power need nuclear fission?

Answer 26

So they can work

• this is triggered by a neutron
• this only works when a slow neutron hits the nucleus

Question 27

Control rod

Answer 27

Control the reaction by absorbing neutrons

• if a reaction is going too fast, they’re lowered so the reaction slows down
• if it’s going too slowly they’re raised so the reaction gets faster

Question 28

Nuclear fission

Answer 28

When a large unstable nucleus splits into two smaller nuclei releasing energy

• a big nucleus can undergo fission because all the protons repel each other
• it needs to absorb a slow neutron to undergo fission