Strontium (Sr) is an alkaline earth metal with atomic number 38, found in Group 2 of the periodic table. In its elemental form, strontium does not form bonds with other atoms in the same way non-metals do, so it doesn’t have a Lewis structure that involves shared or lone pairs of electrons. However, understanding the electron configuration and Lewis symbol for strontium is useful in predicting its reactivity and bonding behavior in compounds.
Lewis Symbol for Strontium (Sr)
The Lewis symbol represents the valence electrons of an atom, which are the electrons in the outermost shell that participate in bonding. Strontium has two valence electrons because it’s in Group 2.
The Lewis symbol for Sr is written as:
This representation shows the two valence electrons of strontium as two dots placed around the symbol “Sr.” These two electrons are relatively easy for strontium to lose, making it a common metal to form ionic bonds.
Lewis Structure of Strontium in Compounds
In most compounds, strontium loses its two valence electrons to form a Sr²⁺ ion. When it does so, it achieves a stable electron configuration like that of a noble gas (krypton).
For example:
- In strontium chloride (SrCl₂), strontium loses two electrons to form Sr²⁺, and each chlorine atom gains one electron, forming Cl⁻ ions. The resulting compound consists of Sr²⁺ ions and Cl⁻ ions held together by ionic bonds.
So, while strontium in its elemental form has a simple Lewis symbol with two dots, in ionic compounds like SrCl₂, it achieves stability by losing these electrons and forming a positively charged ion.
Key Points
- Lewis symbol for Sr: Sr with two dots around it, representing its two valence electrons.
- Ionic behavior: Strontium typically loses its two valence electrons to form Sr²⁺ ions in compounds.
- Common compounds: Strontium often forms ionic compounds like SrCl₂ by transferring its electrons to non-metals.
This understanding of strontium’s Lewis symbol and bonding behavior helps predict its role in various chemical reactions and its tendency to form ionic compounds.