Radioactivity

Question 1

What are 3 elements in the atomic structure?

Answer 1

Atoms, nucleus, electrons

Question 2

What are ions?

Answer 2

Atoms gain electrons to form negative ions

Question 3

What are isotopes?

Answer 3

Atoms with same number of protons but different number neutrons

Question 4

What is the plum pudding model?

Answer 4

Ball of positive charge with negative charge scattered throughout

Question 5

What is the Bohr model?

Answer 5

Central nucleus with electrons orbiting in energy levels

Question 6

What is alpha radiation?

Answer 6

• 2 neutrons + protons (helium nucleus)
• ionising radiation -> damages body cells that causes mutations that lead to cancer

Question 7

What’s gamma radiation?

Answer 7

EM radiation

Question 8

What’s beta radiation?

Answer 8

• Emitted when a neutron turns into a proton in nucleus
• Thickness detectors
• High speed election

Question 9

What’s irradiation?

Answer 9

Object is exposed to radiation without becoming radioactive

Question 10

What’s nuclear fusion?

Answer 10

Joining of two light nuclei into a larger nucleus
- requires very high temperatures and pressure

Question 11

What’s nuclear fission?

Answer 11

• Produces two smaller nuclei and releases energy
• Releases 2 or 3 neutrons
• Splitting of large and unstable nuclei

Question 12

What are 2 types of background radiation?

Answer 12

Man-made
-nuclear weapons testing and nuclear accidents
Natural
-rocks and cosmic rays from space

Question 13

What’s nuclear decay?

Answer 13

when the nucleus of an atom is unstable and emits energy in the form of radiation

Question 14

What will block beta radiation?

Answer 14

Thin sheet of aluminium

Question 15

What will block gamma radiation?

Answer 15

Lead + concrete

Question 16

Which type of radiation is most ionising?

Answer 16

Alpha

Question 17

Which type of radiation is least ionising?

Answer 17

Gamma