Alpha, Beta and Gamma Radiation

Question 1

What are Alpha particles

Answer 1

Helium Nuclei

Question 2

What are Beta particles

Answer 2

Electrons

Question 3

What are gamma rays?

Answer 3

Very short wavelength EM Waves

Question 4

What are alpha particles made up of?

Answer 4

2 protons and 2 neutrons.

Question 5

What are alpha particles?

Answer 5

They are helium nuclei. They’re heavy and slow-moving. They are made up of 2 protons and 2 neutrons. They therefore don’t penetrate far into materials but are stopped quickly

Question 6

Alpha particles are “strongly ionising”. What does this mean? (ionising power)

Answer 6

They bash into a lot of atoms and knock electrons off them before they slow down and create lots of ions.

Question 7

How well do alpha particles penetrate materials?

Answer 7

They are heavy and slow moving. They therefore don’t penetrate far into materials but are stopped quickly

Question 8

Which is the most ionising? Alpha particles, beta particles or gamma rays.

Answer 8

Alpha particles.

Question 9

Which is the least ionising? Alpha particles, beta particles or gamma rays.

Answer 9

Gamma rays

Question 10

Because alpha particles are electrically charged (with a positive charge)……

Answer 10

….alpha particles are deflected (their direction changes) by electric and magnetic fields.

Question 11

What happens to the atomic number and mass number when an alpha particle is emitted?

Answer 11

The atomic number of the nucleus decreases by 2 and the mass number decreases by 4.

Question 12

What is the helium nuclei?

Answer 12

Alpha particles.
He, Mass number 4 and Atomic number 2

Question 13

What is a beta particle?

Answer 13

A beta particle is an electron which has been emitted from the nucleus of an atom when a neutron turns into a proton and an electron.

Question 14

What happens when a beta particle is emitted?

Answer 14

The number of protons in the nucleus is increased by 1. So the atomic number is increased by 1 but the mass number remains the same.

Question 15

How well do beta particles penetrate materials?

Answer 15

They move quite fast and are quite small. Therefore they penetrate moderately before colliding.

Question 16

What is the ionising power of beta particles?

Answer 16

They are moderately ionising. Because they are charged (negatively), beta particles are deflected by electric and magnetic fields.

Question 17

Why are gamma rays the opposite to alpha particles?

Answer 17

They have no mass. They are just energy in the form of an EM wave.

Question 18

How well do gamma rays penetrate materials?

Answer 18

They can penetrate a long way into materials without being stopped.

Question 19

What is the ioning power of gamma rays?

Answer 19

Because they can penetrate a long way into materials, they are weakly ionising as they tend to pass through rather than collide with atoms. But eventually they hit something and do damage.

Question 20

What is the charge of a gamma ray?

Answer 20

They have no charge so they are not deflected by electric or magnetic fields.

Question 21

Gamma rays are not deflected by electric or magnetic fields because…..

Answer 21

….. they have no charge.

Question 22

When does gamma emission occur?

Answer 22

After alpha or beta decay

Question 23

What happens to the atomic number and the mass number after gamma emission?

Answer 23

There is no effect on the atomic or mass numbers of the isotope

Question 24

What happens if a nucleus has excess energy?

Answer 24

it loses this energy by emitting a gamma ray

Question 25

What is the maximum range of a beta particle in air.

Answer 25

50 cm