Answer to Question #86270 in Inorganic Chemistry for ebubechukwu

Question

which element behave partly as the alkaline metals as well as a halogen element

Answer 1

This element is Hydrogen. Hydrogen is a nonmetal and is placed above group in the periodic table because it has ns¹ electron configuration like the alkali metals. However, it varies greatly from the alkali metals as it forms cations (H⁺) more reluctantly than the other alkali metals. Hydrogen‘s ionization energy is 1312 kJ/mol, while lithium (the alkali metal with the highest ionization energy) has an ionization energy of 520 kJ/mol. Because hydrogen is a nonmetal and forms H^- (hydride anions), it is sometimes placed above the halogens in the periodic table. Hydrogen also forms H₂ dihydrogen like halogens. However, hydrogen is very different from the halogens. Hydrogen has a much smaller electron affinity than the halogens.

Reference: https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Supplemental_Modules_(Inorganic_Chemistry)/Descriptive_Chemistry/Elements_Organized_by_Block/1_s-Block_Elements/Group__1%3A_The_Alkali_Metals/Z%3D001_Chemistry_of_Hydrogen_(Z%3D1)