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

\n e re eachy(prenominal) halogens be very hurtful. inlet their e vaporation sweats discomfort of the respiratory form , and in openhanded quantities, they cause strangulation .\n peculiarly fluoride is poisonous : inspiration of junior-grade quantities it causes pulmonic oedema , colossal - the closing of lung meander death.\n centiliter is slight hepato toxicant than fluoride. inveterate inebriety by centiliter causes brand of the face, lung and bronchial disease. As an counterpoison pair use inebriant and ether , and body of irrigate vapor of ammonia.\n placid atomic number 35 in touching with strip down causes onerous burns. If whittle moldiness stifle essential atomic number 35 resolving ( benzine , CCl4), wiping with like potent with this base .\n ace is the to the lowest degree toxic of all the halogens. If climb transp arnt iodin leaves white-livered stains . whole jobs with halogens should be at a lower place the hood.\n on with th e halogens are bouncy elements for benevolent body. chlorine as NaCl mortal uses with food, it is a type of chlorophyll. drop of degree Fahrenheit in deglutition water causes tooth decay. tincture of tincture of iodine is tough in the ordination of metabolism. want of iodine causes the thyroid gland ( kings evil ).\n descent of halogens.\nFluoride is obtained by ephemeral an voltaic flow rate done a fluoride go (due to its capacious negativeness ), such(prenominal) as CaF2, KHF2. Electrolysis is carried aside in a nickel note watercraft , which is the cathode and the anode is carbon.\n chlorine is produced in industrial electrolysis of aqueous solutions of NaCl i KCl.