Net Ionic Equations Pre-AP
The purpose of Net Ionic Equations, (NIE), is to have a balanced equation showing all
chemical species that changed during the reaction. Spectators are not written.
“Changed” includes:

forming a precipitate , (forming an insoluble substance)

forming a new covalent compound, (such as H2O, CO2, O2, H2, etc.)

changing the charge of an element
When writing NIE:
1. Write the complete balanced equation with all symbols, subscripts, and coefficients.
2. Include symbols of state where possible.
aq = dissolved in water; when used with ionic compounds, the compound
breaks into ions
s, l, g = solid, liquid, or gas; can be used with reactants or products
 = a gas is formed ; product only
 = a precipitate is formed ; product only
3. Determine which products represent a “change” and write them down
4. Write the reactant required to form those products.

If a reactant is s, l, or g ; write the entire reactant

If a reactant is a weak acid; write the entire acid, (not just H+)

If a reactant is aq. and soluble, only write the ion you need.
Practice Problems
For each equation below: (1) write the balanced equation, and (2) write the NIE
( Note: all problems below “react”)
 Zinc pellets are mixed with a solution of Stannic Acetate 
2. Iron filings are mixed with aqueous Silver Nitrate 
(iron will form 3+)
 Aqueous solutions of Vanadium(III) Bromide and Ammonium Phosphate mix 
 Solutions of Cobaltous Chlorate and Lithium Carbonate are combined 
 A Barium Chloride solution is added to aqueous Sodium Sulfate 
2
 Aqueous solutions of Potassium Iodide and Mercurous Nitrate are combined 
 Hydrochloric Acid is added to 1.0 M Cesium Carbonate 
 Powdered Chromic Carbonate is added to 3 M Nitric Acid 
 Ammonia gas is bubbled through 0.5 M Perchloric Acid 
 Acetic Acid is combined with dilute Sodium Hydroxide 
 Sulfurous Acid is neutralized with dilute Calcium Hydroxide 
 C3H8 combusts in an oxygen atmosphere 
 Aluminum powder is heated in the presence of Oxygen gas 
 A small piece of Potassium is dropped into a flask of Chlorine gas 
 Sodium Chlorate powder is heated until it decomposes 
 Cupric Hydroxide crystals are heated 