Answer;
Group 2
Explanation;
-Elements in group 2 (alkaline earth metals) have a 2 valence electrons (two electrons in the outermost energy shell). Which means that for these elements to achieve an octet configuration, they will have to loose two electrons. Therefore; element X has a valency electrons, it reacts chlorine to form a compound (XCl2), since chlorine has a valency of 1.
