Is there really a rule or at least a firm guideline that ultimately requires the name of element to end in -ine simply because it has electrons? Or was it somehow necessary to experimentally demonstrate some chemical property associated with halogens?
Or would an atom with electrons certainly and without question behave like a halogen? Or will all current and future elements that obeys certain numerical rules be called halogens no matter how they behave chemically?
Improve this question. Community Bot 1. See: en. Astatine would already be something of an oddball, if only it could be isolated in reasonable amounts.
The discontinuity of the chemical properties between the last common halogen iodine and tennessine would be very stark indeed. Add a comment. Active Oldest Votes. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Share Flipboard Email. Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph. She has taught science courses at the high school, college, and graduate levels.
Facebook Facebook Twitter Twitter. Updated August 02, Key Takeaways: Halogens The halogens are the elements in group 17 of the periodic table. This is the next-to-last column of elements on the righthand side of the table. The halogen elements are fluorine, chlorine, bromine, iodine, astatine, and possibly tennessine. The halogens are highly reactive nonmetallic elements.
They commonly form ionic bonds with metals and covalent bonds with other nonmetals. The halogens are the only group of elements that include elements in all of the three main states of matter: gases, liquids, and solids. Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph. List of Halogens Element Groups.
What Element in the Halide Family is a Liquid? Liquid Elements on the Periodic Table. Organohalogens are also synthesized through the nucleophilic abstraction reaction. Polyhalogenated compounds are industrially created compounds substituted with multiple halogens. Many of them are very toxic and bioaccumulate in humans, but they have many possible applications. Despite its toxicity, fluoride can be found in many everyday products, including toothpaste, vitamin supplements, baby formulas, and even public water.
Many dental products contain fluoride in order to prevent tooth decay, but overconsumption of fluoride can be fatal. Chlorine accounts for about 0. Chlorine is primarily used in the production of hydrochloric acid, which is secreted from the parietal cells in the stomach and is used in maintaining the acidic environment for pepsin.
It plays a vital role in maintaining the proper acid-base balance of body fluids. It is neutralized in the intestine by sodium bicarbonate. Both chlorine and bromine are used as disinfectants for drinking water, swimming pools, fresh wounds, spas, dishes, and surfaces. They kill bacteria and other potentially harmful microorganisms through a process known as sterilization. Chlorine and bromine are also used in bleaching. Sodium hypochlorite, which is produced from chlorine, is the active ingredient of most fabric bleaches.
Chlorine-derived bleaches are also used in the production of some paper products. Iodine is an essential mineral for the body. It is used in the thyroid gland but can also be found in breast tissue, salivary glands, and adrenal glands. Without iodine, thyroid hormones cannot be produced, which leads to a condition called hypothyroidism. Without treatment, the thyroid gland will swell and produce a visible goiter. Children with hypothyroidism may develop mental retardation.
In women, hypothyroidism can lead to infertility, miscarriages, and breast and ovarian cancer. Thyroid problems have been a common issue for many years, particularly in middle aged women; studies correlate this with the fact that iodine levels in the general population have significantly decreased in recent years. Because of certain health problems, many people have been consuming less salt, which usually contains iodine.
In drug discovery, the incorporation of halogen atoms into a lead drug candidate results in analogues that are usually more lipophilic and less water-soluble.
Therefore, halogen atoms are used to improve penetration through lipid membranes and tissues. It follows that there is a tendency for some halogenated drugs to accumulate in adipose tissue.
Polyhalogenated compounds PHCs are of particular interest and importance because halogens are generally highly reactive and bioaccumulate in humans. DDT dichlorodiphenyltrichloroethane is a polyhalogenated pesticide that was banned in the United States in because of the potential harmful effects on human health.
In the second half of World War II, it was used to control malaria and typhus among civilians and troops. The US ban on DDT is cited by scientists as a major factor in the comeback of the bald eagle, the national bird of the United States, from near extinction.
It is now banned in the United States because of its potential harmful effects on human health. Key: chlorine atoms: green, carbon atoms: black, hydrogen atoms: white. PHCs are generally immiscible in organic solvents or water but miscible in some hydrocarbons, from which they are often derived.
PHCs are used in a vast array of products and industries, such as:. Privacy Policy. Skip to main content.
Nonmetallic Elements. Search for:. Halogens Properties of the Halogens Halogens fluorine, chlorine, bromine, iodine, astatine are nonmetal elements that are highly electronegative and reactive.
Learning Objectives Describe the physical and chemical properties of halogens. Down the group, atom size increases. As a diatomic molecule, fluorine has the weakest bond due to repulsion between electrons of the small atoms. Due to increased strength of Van der Waals forces down the group, the boiling points of halogens increase. Therefore, the physical state of the elements down the group changes from gaseous fluorine to solid iodine.
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