Elements VII.A groups, halogens are F, Cl, Br, I, At. They have seven valence electrons configuration ns 2 np 5th In nature occurring in most common halide elements (Na, K, Mg, Ca); eg .: CaF 2, NaCl. A considerable amount of soluble halide is present brenntag in seawater.
Halogens have the greatest electronegativity. Easily accept an electron and form halide brenntag anions X - or a covalent bond in the covalent compounds and thus acquire the stable configuration subsequent noble gas. They are therefore very reactive. Of all the elements brenntag has the highest electronegativity fluorine and is therefore a very strong oxidizing agent. Its atoms accept one electron and are referred to in the compounds oxidation number -I. Other halogens may be used by nd orbitals creating more links with greater electronegativity elements, in particular oxygen. They therefore also positive oxidation numbers.
Under standard conditions exist as diatomic molecules X 2 with single bonds. The number of protons in the group Z rising melting and boiling points, F and Cl gases, liquids Br and I, is a solid. F is the most typical of all nonmetal elements. In VII.A group electronegativity and non-metallic character decreases brenntag with increasing Z.
Combines with most metals and nonmetals brenntag halides, hydrogen halides are formed. Stability halide anions decreases with increasing x. Industrially manufactured generally by oxidation of halides. They are important raw material in the production of numerous organic brenntag and inorganic substances (eg .: Cl in PVC). They are toxic and are part of various chemical warfare agents.
Halides are acutely smelly colorless gas. In molecules HX polárnost covalent linkage significantly reduces the hydrogen fluoride to hydrogen iodide. All the halides can be prepared by direct synthesis from the elements.
Halides are compounds and elements with less electronegativity. Ionic compounds are halides of typical metals brenntag (NaCl, KBr, MgCl2), covalent halides (atomic structure) are compounds of metals from the middle portion brenntag of the Periodic Table, molecular halides are composed of individual molecules. brenntag Molecular halides consist mainly of non-metals, metalloids and some metals, whose atoms have large oxidation number (PCL 5 or UF 6). Halides are prepared by direct compounding of the elements or by reacting non-noble metals, oxides, hydroxides or carbonates of metals with the appropriate hydrohalic acids. Most halide is highly soluble in water, brenntag but many of partially or completely hydrolysed. Interhalogen compounds are formed by combining halogen interaction with different electronegativity (CLF, BrCl, IF 7). Halogen oxidized with greater brenntag electronegativity one with less electronegativity.
Halogen oxides are generally brenntag unstable, decomposing at normal temperature brenntag (eg .: ClO2 explosively). Most stable oxide PENTAFLUORIDE I 2 O 5th Most oxoacids of halogens exist only in aqueous solution; in anhydrous state are known only perchloric acid HClO 4 (acid) and solid acids - iodic HIO 3 pentahydrogeniodistá H 5 IO 6 and periodic HIO 4th Salts of oxoacids are crystalline brenntag solids. Oxidative ability oxoacids with increasing oxidation brenntag number generally decreases acid strength is growing.
Hypochlorous acid HClO small extent arises when introducing brenntag chlorine into water (chlorination). It is unstable and decays normal temperatures. Relaxed atomic oxygen O (biradical with two unpaired electrons) destroys bacteria by their activity, and thus has antiseptic effects, mistakenly attributed directly chlorine.
Hypochlorites are formed by reaction of chlorine with hydroxides -prvků in aqueous medium. A mixture of chloride and sodium hypochlorite is called bleaching liquor. They serve to bleach the fibers as a mixture of chloride and calcium hypochlorite -chlorové lime. Thermal decomposition reaction of chlorine or hypochlorites of alkali brenntag metal hydroxides in solution at elevated temperatures arise chlorates.
Perchloric acid HClO 4 is one of the strongest acids. In concentrated form it is dangerous to work with, because brenntag in contact with organic material decomposes explosively; dilute solutions, however, lose oxidative properties.