Tip:

The charges (+/-) are dropped when superscripts exchange places becoming subscripts.

When 1 becomes a subscript it is not written down. It is assumed to be 1 because the element is written once.

Example

"Criss-Cross" the charges if they do not add up to equal zero. The superscripts become subscripts.

Mg⁺²Cl^-1 + Na⁺¹OH^-1 ---> Mg⁺²OH^-1 + Na⁺¹Cl^-1

Since the superscipts in Mg & Cl do not add up to 0 (+2-1 =1), the 2 and 1 exchange places or criss-cross. By doing so the Mg receives the 1 and the Cl receives the 2. We have applied the same strategy to each ionic compound. After all ions have been criss-crossed we will have:

MgCl2+ NaOH --->Mg(OH)2 + NaCl

Now a correctly written equation is present.

Step 3

Tip:

Example