Answer: m Most likely Group2 metals and Group 17 non-ktta
Explanation:
A little more information is needed to be certain, but the likely answer is that X belongs to Group 2 and Y belongs to Group 17. Group 2 metals (Be, Mg, Ca, Sr, Ba, etc.) are all divalent. They gave rive up 2 electrons each to return to a full shell. Group 17 elements (e,g, F, Cl, Br, I, etc.) all require 1 electron to reach a full valence shell. That would make the proportion 1X to 2Y, or XY2. It is possible that a metal outside of Group 2 would also have a valency of 2. Iron(II) forms FeCl2, for example.
