Question

Elements X and Y have valence shell electron configuration as X=ns2 np5, Y= ns2 np3. Which compound is likely to form between them.

Answer 1

XY2 is likely to form by elements X AND Y

Answer 2

Answer:

According to the periodic table, element X with valence shell electron configuration of ns2np5 is a group 7A element which consists of non-metals termed halogens like fluorine, chlorine, bromine etc.  

Solution:

The halogens, have seven electrons in their highest energy orbital which is one short of the octet and so tends to form anions with -1 charge called as halides.  

The element Y with valence shell electron configuration of ns2np3 belong to group 5A which consists of pnictogens like nitrogen, phosphorus, arsenic, antimony etc. Since they have 3 valence electrons in their outermost shell they form ionic compounds called trihalides.

When element X and Y interact, X can give one electron, so it forms XY3