Metals (m) in group 2 of the periodic table form ionic bonds
with nonmetals (x) present in group leading to
formation of ionic compound with general formula of mx.
a
17
b
16
c
18
d
15

Group 2 metal with form ionic bond with Group 16 elements to form compound with molecular formula MX.

Explanation:

Group 2 elements has 2 in there valence shell. For an element to complete its octet they are required 8 configuration.

Group 16 elements has 6 in there valence shell and they require 2 to complete there octet and form MX ionic compound.

The bonds form between Group 2 and Group 16 metal will complete the octet of both the elements and form MX type of compound.

For example: The reaction of Barium (Ba) (Group 2 element) with Sulphur (S) (Group 16 element) will form Barium sulphide  (BaS), with molecular formula MX.

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16

Explanation:

Group two elements are alkaline earth metal.

All these have two valance electrons. In order to achieve noble gas configuration it loses its two valance and get complete octet.

Reaction with group 16.

Reaction with oxygen,

They react with oxygen and form oxide.

2Ba   +   O₂   →    2BaO

2Mg  +   O₂   →    2MgO

2Ca +   O₂   →    2CaO

this oxide form hydroxide when react with water,

BaO  + H₂O   →  Ba(OH)₂

MgO  + H₂O   →  Mg(OH)₂

CaO  + H₂O   →  Ca(OH)₂

With sulfur,

Mg + S   →  MgS

Ca + S   →  CaS

Ba + S   →  BaS

the atomic mass is the bottom number on the element.

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