which halogen is radioactive?

Answer 1

astatine-last member of halogen

Answer 2

Element 85, Astatine, is a radioactive only halogen.

All the other halogens also have radioactive isotopes.

Answer 3

All can be radioactive but astatine is the main natural radioactive element that is a halogen

Answer 4

astatine

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as·ta·tine (ăs'tə-tēn', -tĭn)
n. (Symbol At)
A highly unstable radioactive element, the heaviest of the halogen series, that resembles iodine in solution. Its longest lived isotope has a mass number of 210 and has a half-life of 8.3 hours. Atomic number 85; melting point 302°C; boiling point 337°C; valence probably 1, 3, 5, 7.

Answer 5

Astatine and isotopes of the other halogens

Answer 6

Fluorine, Bromine and Iodine.

http://www.answers.com/radioactive%20halogens

Answer 7

astatine (At)

(naturally radioactive element)

Answer 8

Iodine

The halogens are a chemical series. They are the elements in Group 17 (old-style: VII or VIIA) of the periodic table: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At) and the as yet undiscovered ununseptium (Uus). The term halogen was coined to mean elements which produce salt in union with a metal. It comes from 18th century scientific French nomenclature based on erring adaptations of Greek roots.

These elements are diatomic molecules in their natural form. They require one more electron to fill their outer electron shells, and so have a tendency to form a singly-charged negative ion. This negative ion is referred to as a halide ion; salts containing these ions are known as halides.

Halogens are highly reactive, and as such can be harmful or lethal to biological organisms in sufficient quantities. Fluorine is the most reactive element in existence, even attacking glass, and forming compounds with the heavier noble gases. It is a corrosive, highly toxic gas. Chlorine and iodine are both used as disinfectants for such things as drinking water, swimming pools, fresh wounds, dishes, and surfaces. They kill bacteria and other potentially harmful microorganisms, a process known as sterilization. Their reactive properties are also put to use in bleaching. Chlorine is the active ingredient of most fabric bleaches and is used in the production of most paper products.

Halide ions combined with single hydrogen atoms form the hydrohalic acids (i.e., HF, HCl, HBr, HI), a series of particularly strong acids. (HAt, or "hydrastatic acid", should also qualify, but it is not typically included in discussions of hydrohalic acid due to astatine's extreme instability toward alpha decay.)

They react with each other to form interhalogen compounds. Diatomic interhalogen compounds (BrF, ICl, ClF, etc.) bear strong superficial resemblance to the pure halogens.

Many synthetic organic compounds such as plastic polymers, and a few natural ones, contain halogen atoms; these are known as halogenated compounds or organic halides. Chlorine is by far the most abundant of the halogens, and the only one needed in relatively large amounts (as chloride ions) by humans. For example, chloride ions play a key role in brain function by mediating the action of the inhibitory transmitter GABA and are also used by the body to produce stomach acid. Iodine is needed in trace amounts for the production of thyroid hormones such as thyroxine. On the other hand, neither fluorine nor bromine are believed to be really essential for humans, although small amounts of fluoride can make tooth enamel resistant to decay.

They show a number of trends when moving down the group - for instance, decreasing electronegativity and reactivity, increasing melting and boiling point.

Iodine-131, also called radioiodine, is a radioisotope of iodine.

Iodine-131 decays with a half-life of 8.0197 days with beta and gamma emissions. An iodine atom has 78 neutrons. On decaying, iodine-131 transforms into xenon-131:



It is used in nuclear medicine both diagnostically and therapeutically. Examples of its use in radiation therapy include the treatment of thyrotoxicosis and thyroid cancer. Diagnostic tests exploit the mechanism of absorption of iodine by the normal cells of the thyroid gland. As an example iodine-131 is one of the radioactive isotopes of iodine that can be used to test how well the thyroid gland is functioning.

Iodine-131 is also used as a radioactive label for radiopharmaceuticals that can be used for imaging and therapy e.g. I131-metaiodobenzylguanidine (I-131-MIBG) for imaging and treating phaeochromocytoma and neuroblastoma.

If iodine-131 is present in high levels in the environment from radioactive fallout, it is absorbed by the body and may cause damage to the thyroid. This can be mitigated by taking iodine supplements, raising the total amount of iodine in the body and therefore reducing uptake end retention in tissues and lowering the relative proportion of radioactive iodine. Such supplements were distributed to the population living nearest to the Chernobyl nuclear power plant after the disaster.

Patients receiving radioiodine treatment are warned not to have sexual intercourse for seven days, not to hug or hold children, a one or two metre distance may be recommended, and women are told not to become pregnant for six months afterwards. These guidelines vary from hospital to hospital and will depend also on the dose of radiation given.

Many airports now have radiation detectors in order to detect the smuggling of radioactive materials that may be used in nuclear weapons manufacture. Patients should be warned that if they choose to travel by air, they may set off radiation detectors at airports up to 12 weeks after their treatment with iodine-131. A physician's letter does not exempt one from interrogation by airport security personnel, because these letters are easily forged. For security reasons, there is no information available in the public domain on which airports use radiation detectors.

Answer 9

astatine