Answer: The complete ionic equation contains
ions
Step-by-step explanation:
Complete ionic equation is defined as the equation in which all the substance that are strong electrolyte are present in an aqueous are represented in the form of ions.
The chemical equation for the reaction of sodium sulfide and magnesium chloride is given as:

Ionic form of the above equation follows:

The complete ionic equation for the above reaction follows:

Hence, the complete ionic equation contains
ions