# Question #cd842

##### 1 Answer
Feb 8, 2014

The ionic bond only forms when the charges between the ions are equal and opposite. The positive charge must be equal of that of the negative anion which means their charges will balance each other out and make the compound neutral.

To form sodium chloride (table salt) the positive sodium cation has a charge of $N {a}^{- 1}$ and the chlorine has a charge of $C {l}^{- 1}$.
because the +1 charge and the -1 charge are equal and opposite they neutralize each other to a zero charge.

In the case of aluminum oxide, the $A {l}^{+ 3}$ cation and the ${O}^{- 2}$ will balance at $A {l}_{2} {O}_{3}$ because the two aluminum ions will create a +6 charge and the three oxide ions will create a -6 charge making them equal and opposite with a total charge of zero or neutral.

I hope this was helpful.
SMARTERTEACHER