They all look like there decaying and was left out or sat inside too long
Calcium is in group 2A because it has two valence electrons and an oxidation state of 2+. Hope this is accurate & helpful! Enjoy your evening.
<h3 /><h3>Answer:</h3>
Option A)
Magnesium chloride, MgCl2, is a binary compound with bonds with relatively high ionic character.
