<h3>What is Alkaline Earth Metal?</h3>
The alkaline earth metals are the elements that correspond to group 2 of the modern periodic table.
All elements of this group forms a cation of +2 charge.
This group involves:
Beryllium (Be), Magnesium(Mg), Calcium (Ca), Strontium (Sr), Barium(Ba) and Radium (Ra).
<h3>What is Halogens?</h3>
The Halogen elements are present in group 17 of the modern periodic table.
All elements of this groups forms anion of -1 charge .
This group involves:
Fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At)
Since , magnesium has +2 cation charge so it reacts with 2 chlorine atoms rather than 1 in order to complete their octate and becomes more stable as chlorine has cahrge of -1.
If one chlorine atom react with magnesium then it does not complete the octet of magnesium and compound becomes unstable.
Hence,
MgCl favored energetically relative to MgCl₂
Learn more about Ionic bond here:brainly.com/question/13526463
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