Unit 2 - Radioactivity

Question 1

What is an isotope and what does it contain?

Answer 1

Isotopes are atoms of an element with the normal number of protons and electrons, but different numbers of neutrons.

Isotopes have the same *atomic *number, but different mass numbers.

Question 2

What is the symbol for Alpha?

Question 3

What is the symbol for Beta?

Question 4

What is the symbol for Gamma?

Question 5

What is the nature of Alpha?

Answer 5

2 protons, 2 neutrons

Question 6

What is the nature of Beta?

Answer 6

Electron

Question 7

What is the nature of gamma?

Answer 7

Electromagetic wave

Question 8

What are Alpha, Beta and Gamma’s charges?

Answer 8

Alpha ** 2+**

Beta -1

Gamma 0

Question 9

What is the mass of Alpha?

Answer 9

Large

Question 10

What is the mass of Beta and Gamma?

Answer 10

Tiny

Question 11

What ionising power does Alpha have?

Answer 11

Huge / Very big

Question 12

What ionising power does Beta have?

Answer 12

Small

Question 13

What ionising powerd does Gamma have?

Answer 13

Tiny

Question 14

What is the penetrating power of Alpha?

Answer 14

Paper / a few cm of air

Question 15

What is the penetrating power of Beta?

Answer 15

A few mm of Aluminium

Question 16

What s the penetration power of Gamma?

Answer 16

Concrete / several cm of lead

Question 17

What is the half life of a radioactiv isotope?

Answer 17

the time taken for;

• The **number of radioactive atoms **

&

• The count rate (no of counts per second)​

To half

Question 18

Isotope

Answer 18

Atoms with the same number of protons but different number of neutrons

Question 19

Radioactive

Answer 19

A raditactive atom is one that emits radiation from its nucleus

Question 20

Radiation

Answer 20

Aplha, Beta and Gamma

Question 21

Definition of Alpha

Answer 21

A helium nucleus

Question 22

Definition of Beta

Answer 22

An electron released from a nucleus

Question 23

Definition of Gamma

Answer 23

An electromgnetic wave/ray

Question 24

Half life

Answer 24

The time it takes for an elements count rate to half

Question 25

Ion

Answer 25

An atom that has lost or gaines electrons

Question 26

Ionising

Answer 26

It can create ions

Question 27

What are the hazards of nuclead radiation?

Answer 27

* Can ionise atoms in our bodies * This can stop/change chemical reactions in our cells * Damage to DNA may cause mutations

Question 28

Symptoms of a low dose of radiation?

Answer 28

Nausea and sickness

Question 29

Symptoms of a moderate dose of radiation?

Answer 29

Skin damage and hair loss

Question 30

Symptoms of a high does of radiation?

Answer 30

Cancers, sterility, death

Question 31

Ways to minimise dosage of radiation?

Answer 31

* Wear a monitor * Reduce exposure * Shield (lead apron, concrete & thick glass) * Remote control handling

Question 32

How is radiation used to kill cancer in the brain?

Answer 32

**Gamma ray treatment** * Lots of low dose beams to minimis the damage of healthy tissure * Aims to kill all the cellls but leave the surrounding tissure unharmed

Question 33

deflection in a magnetic/electric field: Gamma?

Answer 33

Never deflected because it has no charge

Question 34

Deflection in a magnetic/electric field: Alpha?

Answer 34

Isn't deflected much because; * It has a (positive) **charge** * It **has a lot of mass** (to heavy to be moved much by force)

Question 35

Deflection in a magnetic/electric field: Beta?

Answer 35

Deflected because; * Has a (negative) charge * Opposie direction to alpha because it has less mass (the force moves it more because its lighter)

Question 36

Fission

Answer 36

Nuclear fission is the splitting of an atomic nucleus, resulting in the release of large amounts of energy

Question 37

Uncontrolled Chain reaction? Eg bomb

Answer 37


Question 38

Controlled Chain Rection eg nuclear power station

Answer 38


Question 39

Fusion

Answer 39

The joining together of 2 small nuclei to form a nucleus of a larger element, it releases a lot of energy

Question 40

Life cycle of stars?

Answer 40

 Average star - about the same size as the sun