Physical & Chemical Properties of ALKALI Metals I Form 2 Chemistry 

The Secrets of Alkali Metals: A Deep Dive into Group I
Introduction to Alkali Metals
#Alkalimetals exhibit a unique blend of physical and chemical properties that set them apart from other elements. Understanding alkali metals lies in their atomic structure. These elements share a common characteristic: a single #valenceelectron residing in their outermost energy level. This valence electron is the key to their reactivity and distinctive properties.
As we progress down Group 1, from #lithium to #potassium the number of #electrons increases, leading to a larger #atomicradius This trend has profound implications for their chemical behaviour.
Physical Properties
Alkali metals are renowned for their characteristic physical properties. Their lustrous metallic appearance, softness, and #malleability are direct consequences of their atomic structure. The loosely held #valenceelectron allows for easy deformation of the metal lattice, contributing to their softness and #ductility
Moreover, alkali metals exhibit excellent #electricalconductivity due to their mobile #delocalisedelectrons
Density, another crucial physical property, shows an unexpected trend within Group 1. Despite the increase in atomic mass down the group, the #density decreases from lithium to potassium. This is due to the increasing atomic size and the arrangement of #atoms within the metallic structure.
Ionization Energy:
#Ionizationenergy - the energy required to remove an electron from an atom, is a fundamental property that sheds light on an element's reactivity. For alkali metals, the ionization energy decreases progressively as we move down the group. This trend is directly linked to the increasing atomic radius. With each successive element, the valence electron is located farther from the nucleus, experiencing a weaker nuclear attraction. Consequently, less energy is required to remove it.
Reactivity
The alkali metals are renowned for their high reactivity, a direct consequence of their #electronicconfiguration. The single valence electron is readily lost to achieve a stable #octetconfiguration. This tendency to form #cations underlies their vigorous reactions with various substances.
When exposed to air, alkali metals rapidly tarnish due to the formation of #metaloxides.
Their reaction with water is even more dramatic, producing #metalhydroxides and releasing #hydrogen gas. The reactivity increases as we move down the group.
#Halogens the highly reactive non-metals in Group VII readily react with alkali metals to form #ioniccompounds The transfer of electrons from the alkali metal to the halogen results in the formation of ionic bonds, creating stable compounds such as #sodiumchloride (table salt).
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