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...nert form held inside a sealed container. It enables the equipment to last longer and it requires minimum maintenance. b) Name a radioisotope that is used in medicine, describe the way in which it is used, and relate this use to its chemical properties. Technetium-99 is the most widely used radioactive isotope for diagnostic studies in nuclear medicine and it is used in over half of the current nuclear medical procedures. It is a synthetic element, used by doctors to find out how various organs work. -It can be injected into the bloodstream in association with tin compounds and it soon binds to red blood cells. As the blood flows through the heart the tracer allows abnormalities to be detected. Technetium-99 can be changed to many different oxidation states. It is because of this that the production of a wide variety of biologically active chemicals. A biological molecule that concentrates in the organ that is to be investigated is attached to Technetium-99. It is used continuously in gamma ray imaging of the heart, brain and other vital organs. Technetium-99 is used because it has a very short half-life of approximately 6 hours which enables metabolic processes to be examined yet minimises the radiation dose to the patient. It releases low energy gamma radiation that minimises damage to tissues but can still be detected in a person’s body by a gamma ray sensitive camera. It is quickly eliminated from the body. It decays by an ‘isomeric’ process which releases gamma rays and low energy electrons. Since there is not high energy beta emission, the radiation dose to the patient is low. Technetium can be readily excreted from the body. Gamma rays are highly penetrating and consequently greater precautions must be taken when using radioisotopes which produce high energy gamma rays. Eg lead shielding. Question 3 Analyse benefits and problems associated with the use of radioactive isotopes you have identified in Question 2. Cobalt-60 has many benefits in its use in industry as it can test for cracks and flaws that may be in the welds, castings and metal parts and then the structural problem can be fixed because of its detection. Cobalt-60 releases gamma rays and it is the gamma ...