An ionic equation involves an overall reaction between the electrolytes (ions) expressed as dissociated ions in an aqueous solution.
For example, when aqueous solutions of sodium hydroxide and oxalic acid (H2C2O4) are reacted and the net ionic equation for the precipitation reaction occurs when aqueous solutions of nickel(II) acetate and sodium carbonate are mixed.
The net reaction between sodium hydroxide (NaOH) and oxalic acid (H2C2O4):
Hence, this is an example of a net ionic equation.
Method to write the net ionic equation:
The balanced molecular equation with the phases for every compound should be written.
The aqueous salts or the compounds occurring in the equation should be reduced to ions to get the total ionic equation (only the strong electrolytes should be broken down as they dissociate completely)
The final step involves canceling out the spectator ions to derive the net equation.