what element is period 5 group 7a
The correct answer and explanation is:
The element in period 5 and group 7A (or group 17 in modern IUPAC nomenclature) of the periodic table is Iodine (I).
Explanation:
In the periodic table, elements are organized into periods (horizontal rows) and groups (vertical columns). The periods indicate the energy level (or shell) of the electrons, while the groups indicate the number of valence electrons the element has in its outermost shell.
- Period 5 refers to elements that have their electrons filling the 5th energy level (shell).
- Group 7A (Group 17 in IUPAC) is known as the halogens, a group consisting of elements that have seven electrons in their outermost electron shell. These elements are highly reactive, particularly with alkali and alkaline earth metals.
Iodine, with the atomic number 53, is the fifth-period element in group 7A. It shares common properties with the other halogens, such as fluorine, chlorine, bromine, and astatine, like the tendency to form salts when combined with metals. Iodine is a nonmetal and is less reactive than the halogens above it in the group (fluorine, chlorine, and bromine).
Iodine is commonly known for its role in biology, especially in the synthesis of thyroid hormones. The human body requires iodine for proper thyroid function, and its deficiency can lead to goiter and other health issues. In its elemental form, iodine is a solid at room temperature and has a characteristic purple-black color. It is often used in medicine as an antiseptic and in the production of iodized salt to prevent iodine deficiency.
In summary, iodine is the element located in period 5, group 7A (group 17), and is an important halogen with various biological and industrial applications.