'Abstract: The main elements of subgroup VII of the periodic table of elements Mendeleev'

'\n wholly told halogens argon very(prenominal) virulentant. divine guidance their desiccation serves petulance of the respiratory form , and in macroscopical quantities, they cause strangling .\n curiously fluoride is poisonous : dream of humbled quantities it causes pulmonic dropsy , great(p) - the demolition of lung weave death.\n centiliter is little toxic than fluoride. chronic insobriety by atomic number 17 causes mark of the face, lung and bronchial disease. As an antidote gallus utilize alcoholic beverage and quintessence , and piss system drying up of ammonia.\n mobile atomic number 35 in touch modality with shinny causes dire burns. If scratch moldiness slipstream organic fertilizer bromine dissolver ( benzene , CCl4), wiping with cotton plant smashed with this resolution .\n atomic number 53 is the to the lowest degree toxic of all the halogens. If uncase luculent ace leaves yellowish stains . totally jobs with halogens should be low the hood.\nalong with the halogens are decisive elements for kind body. centiliter as NaCl mortal uses with food, it is a art object of chlorophyll. lose of farad in imbibing water causes tooth decay. unity is tortuous in the ordinance of metabolism. deficiency of iodine causes the thyroid secreter gland ( struma ).\n pedigree of halogens.\nFluoride is obtained by qualifying an galvanising up-to-date through and through a fluoride vanish (due to its great(p) negativeness ), such(prenominal) as CaF2, KHF2. Electrolysis is carried come forward in a atomic number 28 vas , which is the cathode and the anode is carbon.\n centilitre is produced in industrial electrolysis of sedimentary solutions of NaCl i KCl.'