![]() ![]() ► Astatine has as many as 37 known isotopes, all of which are radioactive. ► The salts dissolved in sea water are mostly halides of metals, a common example being sodium chloride (NaCl) or table salt. ► There is no double or triple bonds required to explain the concept of bonding in halogens. ► Fluorine, the most reactive element in the periodic table, has no d orbital to expand its valence shell. ► Bromine was first isolated by Balard in 1826. ![]() ► Iodine was discovered in 1811 by Courtois. ► Chlorine was prepared by Scheele in the late 1700s, and it was proved to be an element by Davy in 1810. ► Fluorine, a highly toxic element, was isolated in 1886 by Henri Moissan. ► Bromine is the only non-metal that is liquid at room temperature. ► Fluorine is the first element of the halogen family, and also the most abundant, while astatine is the rarest. Compounds containing halogens are used in fire retardants. Its radioactive isotope is used in medical tracker technologyīromine and iodine are added to halogen lamps to lengthen the life of the filament.Reacts with silver to form silver iodide, which is used in photography.Used in the manufacturing of printing inks. ![]() Added in small amounts to table salt to prevent thyroid disease.Used in the manufacturing of flame retardants.Used in the manufacturing of light-sensitive components used in photographic emulsion.Used in the manufacturing of pharmaceuticals.Hydrogen chloride (HCl), an important industrial product, is prepared by using chlorine as its main component.Chlorine dioxide (ClO 2) is used in the paper industry to bleach wood pulp.It’s used in the manufacturing of common salt or sodium chloride (NaCl).It is added to the water used in public swimming pools. One of the important uses of chlorine is in the manufacturing of disinfectants.Used to manufacture chlorofluorocarbons which serve the purpose of cooling agents in refrigerators.Used as an ingredient in toothpaste, to strengthen tooth enamel and prevent tooth decay.Used in Teflon coating on non-stick cookware.Here are a few important uses of halogen group elements. UsesĮxcept astatine, all elements of the family find extensive use in industries. Halogens form polar covalent compounds with non-metals and metals with higher oxidation states. The reason for this is that as one moves down the group, the size of the halide ion increases, and the ions are more readily polarized. However, as one moves down the group, the covalent character of the halides increases and ionic character decreases. Halogens react with metals to form metal halides that are predominantly ionic. Thus, iodine exhibits certain metallic properties. The halogens, due to their high ionization energies, exhibit non-metallic character, which decreases as one moves down the group. This is due to the increasing distance of the valence electron from the nucleus. However, when we move down the group, we find that the value of ionization energy increases. They act as very strong oxidizing agents due to their high electronegativity.Īll members of the halogen group have very high ionization energies. Since there are seven electrons in the outermost shell of halogens, the oxidation number for these elements is -1. Halogens mostly undergo oxidation-reduction reactions. All halogens, except fluorine, exhibit multiple oxidation states. Among the halogens, fluorine is the most electronegative. The halogens are the elements with the highest electronegativity in the periodic table. This is due to the small atomic radius of the fluorine atom.Įlectronegativity is defined as the ability of the atom of one element to remove an electron from an atom of another element. An interesting thing to note here is that the electron affinity of fluorine is less than that of chlorine. However, as one moves down the group, the electron affinity goes on decreasing as the size of the atom goes on increasing. This is because they have seven electrons in their outermost shells and are keen to achieve the octet configuration of noble gases. The electron affinity for halogens is extremely high, which means they readily accept electrons. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |