Flashcards in Uses of Radioisotopes Deck (12)
What are radioisotopes?
Isotopes of elements that are radioactive
What are the medical uses of radioisotopes?
Gamma rays used to destroy cancerous tissue
Gamma radiation used to sterilise medical instruments
Iodine-131 which emits beta particles is used to measure the uptake of iodine by the thyroid gland
How is gamma radiation used to destroy cancerous tissue?
A controlled dose of gamma radiation is used in radiotherapy to destroy cancer cells without damaging healthy tissue
How is gamma radiation used to sterilise medical instruments?
Instruments are sealed in plastic bags and irradiated with gamma radiation which destroys all microorganisms resulting in sterile equipment
How is iodine-131 which emits beta particles used the measure the uptake of iodine by the thyroid gland?
The patient ingests food containing iodine-131 which has a half-life of eight days
By measuring the amount of radioactivity in the thyroid gland doctors can tell how much of the iodine-131 has been taken up by the gland
What is radiocarbon dating (carbon-14 dating)?
It is a technique used to determine the age of an object containing carbon.
It is based on the ratio of carbon-14 to carbon-12 in the object
How are radioisotopes used in agricultural research?
Phosphorus-32 is used in 'tracer studies' when studying the uptake of fertiliser by a plant
A fertiliser containing phosphorus-32 is fed to a plant
By measuring the radioactivity of the leaves of the plant, scientists can find out how much of the fertiliser has reached them.
How are radioisotopes used in food irradiation?
Food is irradiated with gamma rays to destroy microorganisms responsible for food spoilage and food poisoning
How are radioisotopes used in smoke alarms?
Americum-241 emits alpha particles which allow a small current to flow into the smoke alarm
If smoke enters the alarm the alpha particles are absorbed and the current is reduced which causes the the alarm to sound
How are radioisotopes used in industry?
Leaks in water pipes can be located without digging by adding a radioisotope at one end of the pipeline
The ground can then be rested for any leaking radioisotope using a Geiger-Muller counter
List the three main uses of radioisotopes?