ABSTRACT
The halogens-uorine, chlorine, bromine, iodine, and the astatine-form the 17 or (VIIa) column of the periodic table of elements. There is only one isotope of uorine and iodine in nature; however, chlorine and bromine have two natural isotopes (35Cl-75.77% and 37Cl-24.23%; 79Br−50.69%, 81Br-49.31%). Astatine does not occur in nature or in water samples in a detectable concentration. Different radioactive astatine isotopes with short life time are formed in natural radioactive decomposition reactions; however,
8.1 Introduction: Physical and Chemical Properties ..........................................................................189 8.2 Determination of Halogens and Their Derivatives in Water Analysis ........................................ 190
8.2.1 Active Chlorine ................................................................................................................191 8.2.1.1 Detection .......................................................................................................... 192 8.2.1.2 Quantitative Determination of Free Chlorine in Water Samples .................... 192
8.2.2 Chlorine Dioxide ............................................................................................................. 199 8.2.2.1 Chlorine Dioxide Determination ..................................................................... 199
8.2.3 Chloride ........................................................................................................................... 202 8.2.3.1 Detection .......................................................................................................... 203 8.2.3.2 Determination .................................................................................................. 203
8.2.4 Fluoride ............................................................................................................................ 209 8.2.4.1 Detection ...........................................................................................................210 8.2.4.2 Quantitative Determination of Fluoride Content in Water Samples ................210
