Question

Halogens are strong _____ agents because they ____ electrons to complete their octet.

• A. oxidizing
• B. accept

Answer 1

• Valence electrons of an element is defined as the number of electrons present in the outermost shell of that element.
• Valence electrons in any element in Group 1, 2, and 13 to 18 can be predicted by its Group number. Example, elements in Group 1 or Group IA have 1 valence electron.
• Elements present in Group 17 or VIIA of the periodic table are termed as halogens. It includes Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), Astatine (At), and Tennessine (Ts).
• Since halogens are present in Group 17 or VIIA , they all have seven valence electrons in their outermost shell.
• Oxidizing agents are the ones that themselves undergo reduction (gain of electrons) and oxidize the other species.
• Since halogens have seven valence electrons, they will readily gain one electron and undergo reduction to complete their octet (eight electrons in the valence shell). Hence, they are classified as strong oxidizing agents.
• Example, the electronic configuration of Fluorine is 2, 7. Fluorine (F) readily gains one electron to form a Fluoride ion (F^-). The electronic configuration of the Fluoride ion becomes 2,8. Since the Fluoride ion has a complete octet and therefore, Fluorine acts as a strong oxidizing agent.
• Halogens are strong oxidizing agents because they accept electrons to complete their octet.