Atomic, Nuclear And Radioactivity

Question 1

What is radioactivity

Answer 1

An attempt by an unstable nuclei to achieve greater stability

Question 2

What happens when an alpha particle decays

Answer 2

The nucleus loses two protons and two neutrons. Z goes down by two and A goes down by 4.

Question 3

What happens when a beta particle is emitted

Answer 3

The nucleus has one more proton and one less neutron. The atomic mass number remains unchanged and the atomic number increases
By 1.

Question 4

Decay equation for alpha

Answer 4

219 215 4

86 RN —> 84 Po + 2 He

Question 5

Decay equation for beta

Answer 5

14 14 0

6 C —> 7 N + -1 e

Question 6

Explanation of gamme decay

Answer 6

Gamma decay is the most penetrating of the three. The nucleus changes from higher energy state to a lower energy state through short x-rays of electromagnetic radiation. The number of protons and neutrons doesn’t change.

Question 7

What is half life

Answer 7

Time for number of active nuclei to halve or decay

Question 8

What is activity

Answer 8

The number of of disintegrations per second, directly proportional to the number of undecayed nuclei.
Measured in becquerel(Bq)

Question 9

What is background radiation

Answer 9

Radiation which is ever present in the environment due to natural and artificial sources.

Question 10

What is dose and dose equivalent

Answer 10

Dose equivalent takes into account the nature of the radiation and how ionizing it is.
Dose equivalent = quality factor x absorbed dose

Question 11

Safety precautions

Answer 11

• stores in lead-lined boxes in a locked cabinet within a locked stores room
• use tweezers and tongs, held at arms length
• use safety screens and wear safety goggles

Question 12

Difference between fission and fusion

Answer 12

Fission is splitting of large nuclei, fusion is the joining together of two light nuclei.

Question 13

Advantages of fusion over fission

Answer 13

Fusion is much easier to control whereas fission can lead to a chain reaction being very difficult to stop.

Question 14

Arguments for nuclear energy

Answer 14

• cause less damage to the environment than power stations, do not produce sulfur oxide(no acid rain)
• amount of radioactive waste is very small, can be safely stored underground.
• the world needs more energy, renewable source. Solar, wind and wave don’t give us enough energy

Question 15

Arguments against nuclear energy

Answer 15

• produce waste which stays very radioactive for thousands of years
• storing the waste beneath the ground could lead to a leak.
• spend money on ways to save our energy