Atoms , Neutrons And Ions

Question 1

Why are all atoms neutrally charged?

Answer 1

All atoms are neutrally charged so the atomic number also tells us the number of electrons

Question 2

What is an isotope?

Answer 2

An element with the same number of protons but different number of neutrons

Question 3

What’s an ion?

Answer 3

If an atom gains or loses an electron it becomes an ion.

If it gains electrons it becomes a negative ion

If it loses electrons it becomes a positive ion

Question 4

What are alpha particles?

Answer 4

Alpha particles are Helium Nuclei

1) Alpha radiation is when an alpha particle is emitted from the nucleus
2) They don’t penetrate very far into materials and are stoped quickly - they can only travel a few cm in air and are absorbed by a sheet of paper
3) because of their size they are strongly ionising

Question 5

What is a Beta particle

Answer 5

Beta particles are High-Speed Electrons.

1) Beta is a fast moving electron which is emitted as a result of a neutron turning into a proton inside the nucleus

Question 6

What is gamma radiation?

Answer 6

Gamma is Simply s proton of energy (wave of energy) it is released to channel away energy from an excited nucleus

Question 7

What can alpha radiation be used for ?

Answer 7

Used in smoke detectors- it ionises air particles, causing a current to flow.

If there is smoke in the air , it binds to the ions - meaning current stops and the alarm sounds

Question 8

What are beta emitters used for ?

Answer 8

Used to test the thickness of sheets of metal ,

as the particles are not immediately absorbed by the material like alpha radiation would be

and do not penetrate as far as gamma rays

Question 9

What is half life ?

Answer 9

The time taken for the number of radioactive nuclei in a isotope to halve