GROUP 17 HALOGEN FAMILY

Iodine [7553-56-2] I, atomic number 53, atomic weight 126.9044, is a nonmetaUic element belonging to the halogen family in Group 17 (VIIA) of the Periodic Table. The only stable isotope has a mass number of 127. There are 22 other iodine isotopes having masses between 117 and 139 14 of these isotopes yield significant radiation. 

Halogen family—Group of elements in the periodic table consisting of fluorine, chlorine, bromine, iodine, and astatine. 

Astatine is a member of the halogen family, elements in Group 17 (VlIA) of the periodic table. It is one of the rarest elements in the universe. Scientists believe that no more than 25 grams exist on Earth s surface. All isotopes of astatine are radioactive and decay into other elements. For this reason, the element s properties are difficult to study. What is known is that it has properties similar to those of the other halogens—fluorine, chlorine, bromine, and iodine. Because it is so rare, it has essentially... 

Bromine is a member of the halogen family. Halogens are the elements that make up Group 17 (VIIA) of the periodic table. The periodic table is a chart that shows how elements are related to one another. The word halogen means salt-former. Fluorine, chlorine, bromine, iodine, and astatine form salts when chemically combined with a metal. 

Haloalkanes are alkanes that contain one or more members of the halogen family. The halogens found in organic molecules are chlorine, bromine, fluorine, and iodine. Haloalkanes are the first type of functional group discussed in this book. 

The columns of elements in the periodic table are called groups or families. The elements of a particular family share many similarities in physical and chemical properties because of the similarities in electronic structure. Some of the most important groups are named for example, the alkali metals (lA or 1), alkaline earth metals (IIA or 2), the halogens (VIIA or 17), and the noble gases (VIII or 18). 

Chlorine is a member of Group 7, the halogen family. All of the elemental forms of the Group 7 elements contain diatomic molecules. Fluorine is a pale yellow gas containing F2 molecules. 

Iodine is a nonmetallic element, the fourth member of the halogen family, i.e., Group VII of the Periodic Table, which also includes fluorine, chlorine, bromine, and astatine. Iodine has the atomic number 53, an atomic mass of 127, and only one stable isotope in the Earths crust, though 23 isotopes have been recorded. 

The Periodic Table is organized into vertical colnmns, called groups or families, and horizontal rows, called periods. Gronps are nnmbered from left to right on the table from 1-18. Periods are numbered from top to bottom on the table from 1-7. The vertical colnmns of the Periodic Table contain elements that have similar chemical characteristics in their pure elemental form. These elements have the same nnmber of electrons in the outer shell, which is why they have similar chemical behaviors. These similar elements are sometimes referred to as families. Some of the more important families include the alkali metals in column 1, the alkaline-earth metals in colnmn 2, the halogens in column 7, and the noble or inert gases in colnmn 8. The transition elanents in the center of the Periodic Table are also similar in that most of them have the possibility of differing numbers of electrons in their onter shells. 

The halogens can be found in Group 17. Halogens combine readily with metals to form salts. Table salt, fluoride toothpaste, and bleach all have an element from the halogen family. 

Group 7 The halogen family of active nonmetals. All have seven electrons in the outer shell, and stable inner shells. 

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