An atom X has three electrons in its outermost shell. Which ion will most likely be formed by X?

A. X2-

B. X3-

C. X2+

D. X3+

X3+

Explanation:

Every atom aim to achieve stability by receiving electrons or giving their valence electrons in order to have a complete outermost shell of 2 (duplet) or 8 (octet structure).

In this case, the atom X will easily give off its three valence electrons to another atom(s), thereby forming a trivalent positive ion (X3+) with a stable duplet or octet structure (i.e an outermost shell with 2 or 8 electrons).

X --> X3+ + 3e-

Thus, due to the give away of three electrons (3e-), the atom X becomes X3+.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-