4. Periodic Table and Periodicity of Properties

Define halogens.

Halogens are elements found in Group VIIA (17) of the periodic table. These elements include fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). Halogens are highly reactive, especially with alkali metals and alkaline earth metals, and readily form salts such as sodium chloride (NaCl). Related Questions: Write the valence shell electronic configuration … Read more

Write the valence shell electronic configuration of an element present in the 3rd period and Group IIA.

An element in the 3rd period and Group IIA is Magnesium (Mg). Its atomic number is 12, and its electronic configuration is:1s² 2s² 2p⁶ 3s².This indicates that the valence electrons are in the 3s orbital, with two electrons. Related Questions: Define halogens. Which atom has a higher shielding effect, Li or Na? Explain why Na … Read more