Topic 12 - Nuclear Chemistry Flashcards
(26 cards)
Provide two examples of non-radioactive radiation in our environment.
Visible light, radio waves, infrared light
These types of radiation do not involve radioactive decay.
What is background radiation? Provide 2 examples:
Natural and human-made sources of radiation we are exposed to every day, from our diets, nuclear reactors, the sun’s rays, soil and rocks.
What does a chemical change always involve?
Bond breaking / bond making
What does a nuclear change always involve?
Changes to the nucleus of an atom
What is non-ionising radiation?
Low energy radiation that does not cause atoms/molecules to lose electrons
What is ionising radiation?
High energy radiation that causes electrons to be lost from atoms/molecules
Name the three types of radiation which may be emitted during a nuclear reaction.
Alpha, Beta, Gamma
Describe alpha radiation.
Symbol: He or α
Charge: 2+
Mass: 4
Describe beta radiation.
Symbol: e or β
Charge: 1-
Mass: 0
Describe gamma radiation.
Symbol: γ
Charge: 0
Mass: 0
Which of the three forms is the most penetrative radiation? Which is the least?
Gamma is the most penetrative and alpha is the least
Which of the three types of radiation is described as non-particulate?
Gamma is not made up of particles
Which type of radiation is unaffected when passed through an electric field with positively and negatively charged plates?
Gamma as it has no charge
Write the nuclide notation for an alpha particle.
4
He –> α particle
2
Write the nuclide equation which represents the Th-232 isotope emitting an alpha particle.
232 228 4
Th → Ra + He
90 88 2
In any alpha emission (decay)…
a new isotope is formed with a mass number smaller by 4 units and an atomic number reduced by 2 units. In alpha emission a new element is always formed.
Write the nuclide notation for a beta particle.
0
e
-1
Write the nuclide equation which represents the P-32 isotope emitting a beta particle.
32 32 0
P → S + e
15 16 -1
In any beta emission (decay)…
a new isotope is formed with a mass number which remains the same as original isotope. The new atomic number has increased by 1 unit. This means that in beta emission a new element is always formed.
Why is it not possible to represent the emission of gamma radiation by using a nuclide equation?
There is no change to the isotope other than a loss of energy.
What is the meaning of the term radioisotope?
An isotope that has an unstable nucleus and can undergo decay.
In relation to radioisotopes, what is the definition of the term half-life?
The time for half of the nuclei of a particular isotope to decay.
What is carbon dating?
Using the half-life of carbon-14 to calculate the age of an organic material. The half-life of carbon-14 is 5700 years.
List some uses of the following radioisotopes in medicine:
cobalt-60
radioisotopes of iodine
sodium-24.
- Cobalt-60 is used in radiotherapy
- Radioisotopes of iodine are used to monitor the thyroid gland
- Sodium-24 is used to trace the flow of liquids around the body.
