Net Ionic Equation Examples in Chemistry

Start with the recap, study the fully worked examples, then use the practice problems to check your understanding of Net Ionic Equation.

This page combines explanation, solved examples, and follow-up practice so you can move from recognition to confident problem-solving in Chemistry.

Concept Recap

A simplified chemical equation that shows only the ions and molecules directly involved in a chemical reaction, with all spectator ions (those unchanged on both sides) removed.

Strip away the bystanders. Some ions just float around doing nothing — the net ionic equation shows only the ones that actually react.

Read the full concept explanation →

How to Use These Examples

  • Read the first worked example with the solution open so the structure is clear.
  • Try the practice problems before revealing each solution.
  • Use the related concepts and background knowledge badges if you feel stuck.

What to Focus On

Core idea: Net Ionic Equation starts by comparing the reactant-product pattern, charges, states, and conserved atoms.

Common stuck point: Students often know a formula related to net ionic equation but skip the recognition step: Does the balanced equation match a recognizable pattern of reactants, products, ions, oxygen, or electron transfer? That leads to a correct-looking substitution attached to the wrong chemical model.

Sense of Study hint: Ask: Does the balanced equation match a recognizable pattern of reactants, products, ions, oxygen, or electron transfer?

Worked Examples

Example 1

easy
Explain the difference between a molecular equation, a complete ionic equation, and a net ionic equation. Use the reaction of NaCl(aq)+AgNO3(aq)\text{NaCl(aq)} + \text{AgNO}_3\text{(aq)} as an example.

Answer

Ag+(aq)+Cl−(aq)→AgCl(s)\text{Ag}^+\text{(aq)} + \text{Cl}^-\text{(aq)} \rightarrow \text{AgCl(s)}

First step

1
Molecular equation shows all species as complete formulas: NaCl(aq)+AgNO3(aq)→AgCl(s)+NaNO3(aq)\text{NaCl(aq)} + \text{AgNO}_3\text{(aq)} \rightarrow \text{AgCl(s)} + \text{NaNO}_3\text{(aq)}.

Full solution

  1. 2
    Complete ionic equation splits all aqueous ionic compounds into their ions: Na+(aq)+Cl−(aq)+Ag+(aq)+NO3−(aq)→AgCl(s)+Na+(aq)+NO3−(aq)\text{Na}^+\text{(aq)} + \text{Cl}^-\text{(aq)} + \text{Ag}^+\text{(aq)} + \text{NO}_3^-\text{(aq)} \rightarrow \text{AgCl(s)} + \text{Na}^+\text{(aq)} + \text{NO}_3^-\text{(aq)}.
  2. 3
    Net ionic equation removes spectator ions (Na+\text{Na}^+ and NO3−\text{NO}_3^-) that appear unchanged on both sides: Ag+(aq)+Cl−(aq)→AgCl(s)\text{Ag}^+\text{(aq)} + \text{Cl}^-\text{(aq)} \rightarrow \text{AgCl(s)}.
The net ionic equation shows only the species that actually participate in the chemical change. Spectator ions are present in solution but do not undergo any change — they merely 'watch' the reaction.

Example 2

medium
Write the net ionic equation for the reaction between BaCl2(aq)\text{BaCl}_2\text{(aq)} and Na2SO4(aq)\text{Na}_2\text{SO}_4\text{(aq)}.

Example 3

medium
Write the net ionic equation for Mg(s)+2HCl(aq)→MgCl2(aq)+H2(g)\text{Mg(s)} + 2\text{HCl(aq)} \rightarrow \text{MgCl}_2\text{(aq)} + \text{H}_2\text{(g)}.

Example 4

medium
Write the net ionic for the reaction of NaHCO3(aq)\text{NaHCO}_3\text{(aq)} with HCl(aq)\text{HCl(aq)}.

Example 5

hard
Determine the net ionic equation for AgNO3(aq)+Na3PO4(aq)→Ag3PO4(s)+NaNO3(aq)\text{AgNO}_3\text{(aq)} + \text{Na}_3\text{PO}_4\text{(aq)} \rightarrow \text{Ag}_3\text{PO}_4\text{(s)} + \text{NaNO}_3\text{(aq)}.

Example 6

hard
Write the net ionic for Zn(s)+CuSO4(aq)→ZnSO4(aq)+Cu(s)\text{Zn(s)} + \text{CuSO}_4\text{(aq)} \rightarrow \text{ZnSO}_4\text{(aq)} + \text{Cu(s)}.

Practice Problems

Try these problems on your own first, then open the solution to compare your method.

Example 1

medium
Write the net ionic equation for the neutralization of hydrochloric acid with sodium hydroxide: HCl(aq)+NaOH(aq)→NaCl(aq)+H2O(l)\text{HCl(aq)} + \text{NaOH(aq)} \rightarrow \text{NaCl(aq)} + \text{H}_2\text{O(l)}.

Example 2

hard
Write the net ionic equation for the reaction: K2CO3(aq)+2HCl(aq)→2KCl(aq)+H2O(l)+CO2(g)\text{K}_2\text{CO}_3\text{(aq)} + 2\text{HCl(aq)} \rightarrow 2\text{KCl(aq)} + \text{H}_2\text{O(l)} + \text{CO}_2\text{(g)}. Identify all spectator ions.

Example 3

easy
What does a net ionic equation show?

Example 4

easy
What are spectator ions?

Example 5

easy
Which species are written as separate ions in an ionic equation?

Example 6

easy
Should a precipitate (s)(s) be split into ions?

Example 7

easy
In Ag++Cl−→AgCl(s)Ag^+ + Cl^- \rightarrow AgCl(s), is this already a net ionic equation?

Example 8

easy
Why must a net ionic equation balance charge as well as atoms?

Example 9

easy
In NaCl(aq)+AgNO3(aq)NaCl(aq) + AgNO_3(aq), which ions are spectators when AgCl precipitates?

Example 10

easy
Are state symbols needed to write net ionic equations?

Example 11

medium
Write the net ionic equation for AgNO3(aq)+NaCl(aq)→AgCl(s)+NaNO3(aq)AgNO_3(aq) + NaCl(aq) \rightarrow AgCl(s) + NaNO_3(aq).

Example 12

medium
Net ionic equation for HCl(aq)+NaOH(aq)→NaCl(aq)+H2O(l)HCl(aq) + NaOH(aq) \rightarrow NaCl(aq) + H_2O(l)?

Example 13

medium
Net ionic for BaCl2(aq)+Na2SO4(aq)→BaSO4(s)+2NaCl(aq)BaCl_2(aq) + Na_2SO_4(aq) \rightarrow BaSO_4(s) + 2NaCl(aq)?

Example 14

medium
Verify charge balance: Ba2++SO42−→BaSO4(s)Ba^{2+} + SO_4^{2-} \rightarrow BaSO_4(s).

Example 15

medium
Should weak acid acetic acid CH3COOHCH_3COOH be split in a net ionic equation?

Example 16

medium
Net ionic for Na2CO3(aq)+CaCl2(aq)→CaCO3(s)+2NaCl(aq)Na_2CO_3(aq) + CaCl_2(aq) \rightarrow CaCO_3(s) + 2NaCl(aq)?

Example 17

medium
Why are spectator ions left out of the net ionic equation?

Example 18

medium
In 2HCl+CaCO3(s)→CaCl2+H2O+CO22HCl + CaCO_3(s) \rightarrow CaCl_2 + H_2O + CO_2, why is CaCO3CaCO_3 kept whole?

Example 19

medium
Net ionic for Pb(NO3)2(aq)+2KI(aq)→PbI2(s)+2KNO3(aq)Pb(NO_3)_2(aq) + 2KI(aq) \rightarrow PbI_2(s) + 2KNO_3(aq)?

Example 20

challenge
Write the balanced net ionic equation for 3CaCl2(aq)+2Na3PO4(aq)→Ca3(PO4)2(s)+6NaCl(aq)3CaCl_2(aq) + 2Na_3PO_4(aq) \rightarrow Ca_3(PO_4)_2(s) + 6NaCl(aq).

Example 21

challenge
Net ionic for Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)Zn(s) + 2HCl(aq) \rightarrow ZnCl_2(aq) + H_2(g).

Example 22

challenge
Verify the net ionic 3Ca2++2PO43−→Ca3(PO4)2(s)3Ca^{2+} + 2PO_4^{3-} \rightarrow Ca_3(PO_4)_2(s) balances atoms and charge.

Example 23

easy
Write the net ionic equation for AgNO3(aq)+KCl(aq)→AgCl(s)+KNO3(aq)\text{AgNO}_3\text{(aq)} + \text{KCl(aq)} \rightarrow \text{AgCl(s)} + \text{KNO}_3\text{(aq)}.

Example 24

easy
In Na2SO4+BaCl2→BaSO4+2NaCl\text{Na}_2\text{SO}_4 + \text{BaCl}_2 \rightarrow \text{BaSO}_4 + 2\text{NaCl}, identify the spectator ions.

Example 25

easy
Write the net ionic equation for 2NaOH(aq)+H2SO4(aq)→Na2SO4(aq)+2H2O(l)2\text{NaOH(aq)} + \text{H}_2\text{SO}_4\text{(aq)} \rightarrow \text{Na}_2\text{SO}_4\text{(aq)} + 2\text{H}_2\text{O(l)}.

Example 26

easy
Is H2O(l)\text{H}_2\text{O(l)} a strong electrolyte to be split into ions?

Example 27

medium
Write the net ionic equation for Pb(NO3)2(aq)+2NaCl(aq)→PbCl2(s)+2NaNO3(aq)\text{Pb(NO}_3)_2\text{(aq)} + 2\text{NaCl(aq)} \rightarrow \text{PbCl}_2\text{(s)} + 2\text{NaNO}_3\text{(aq)}.

Example 28

medium
Write the net ionic equation for NH3(aq)+HCl(aq)→NH4Cl(aq)\text{NH}_3\text{(aq)} + \text{HCl(aq)} \rightarrow \text{NH}_4\text{Cl(aq)}.

Example 29

medium
Write the net ionic equation for CaCO3(s)+2HCl(aq)→CaCl2(aq)+H2O(l)+CO2(g)\text{CaCO}_3\text{(s)} + 2\text{HCl(aq)} \rightarrow \text{CaCl}_2\text{(aq)} + \text{H}_2\text{O(l)} + \text{CO}_2\text{(g)}.

Example 30

medium
Write the net ionic equation for CuSO4(aq)+Fe(s)→FeSO4(aq)+Cu(s)\text{CuSO}_4\text{(aq)} + \text{Fe(s)} \rightarrow \text{FeSO}_4\text{(aq)} + \text{Cu(s)}.

Example 31

medium
Net ionic for HF(aq)+NaOH(aq)→NaF(aq)+H2O(l)\text{HF(aq)} + \text{NaOH(aq)} \rightarrow \text{NaF(aq)} + \text{H}_2\text{O(l)}.

Example 32

medium
Net ionic for FeCl3(aq)+3NaOH(aq)→Fe(OH)3(s)+3NaCl(aq)\text{FeCl}_3\text{(aq)} + 3\text{NaOH(aq)} \rightarrow \text{Fe(OH)}_3\text{(s)} + 3\text{NaCl(aq)}.

Example 33

medium
Net ionic for Cu(NO3)2(aq)+2NaOH(aq)→Cu(OH)2(s)+2NaNO3(aq)\text{Cu(NO}_3)_2\text{(aq)} + 2\text{NaOH(aq)} \rightarrow \text{Cu(OH)}_2\text{(s)} + 2\text{NaNO}_3\text{(aq)}.

Example 34

medium
Net ionic for NH4Cl(aq)+NaOH(aq)→NaCl(aq)+NH3(g)+H2O(l)\text{NH}_4\text{Cl(aq)} + \text{NaOH(aq)} \rightarrow \text{NaCl(aq)} + \text{NH}_3\text{(g)} + \text{H}_2\text{O(l)} (warm).

Example 35

hard
Write the net ionic for 2Al(s)+6HCl(aq)→2AlCl3(aq)+3H2(g)2\text{Al(s)} + 6\text{HCl(aq)} \rightarrow 2\text{AlCl}_3\text{(aq)} + 3\text{H}_2\text{(g)}.

Example 36

hard
Net ionic for 2HNO3(aq)+Ba(OH)2(aq)→Ba(NO3)2(aq)+2H2O(l)2\text{HNO}_3\text{(aq)} + \text{Ba(OH)}_2\text{(aq)} \rightarrow \text{Ba(NO}_3)_2\text{(aq)} + 2\text{H}_2\text{O(l)}.

Example 37

hard
Does mixing NaNO3(aq)\text{NaNO}_3\text{(aq)} and KCl(aq)\text{KCl(aq)} produce a net ionic reaction?

Example 38

hard
Net ionic for Sr(NO3)2(aq)+K2SO4(aq)→SrSO4(s)+2KNO3(aq)\text{Sr(NO}_3)_2\text{(aq)} + \text{K}_2\text{SO}_4\text{(aq)} \rightarrow \text{SrSO}_4\text{(s)} + 2\text{KNO}_3\text{(aq)}.

Example 39

hard
Net ionic for CH3COOH(aq)+NaOH(aq)→CH3COONa(aq)+H2O(l)\text{CH}_3\text{COOH(aq)} + \text{NaOH(aq)} \rightarrow \text{CH}_3\text{COONa(aq)} + \text{H}_2\text{O(l)}.

Example 40

hard
Verify both atom and charge balance for Ba2+(aq)+2OH−(aq)+2H+(aq)+SO42−(aq)→BaSO4(s)+2H2O(l)\text{Ba}^{2+}\text{(aq)} + 2\text{OH}^-\text{(aq)} + 2\text{H}^+\text{(aq)} + \text{SO}_4^{2-}\text{(aq)} \rightarrow \text{BaSO}_4\text{(s)} + 2\text{H}_2\text{O(l)}.

Example 41

challenge
For the reaction 5Fe2+(aq)+MnO4−(aq)+8H+(aq)→5Fe3+(aq)+Mn2+(aq)+4H2O(l)5\text{Fe}^{2+}\text{(aq)} + \text{MnO}_4^-\text{(aq)} + 8\text{H}^+\text{(aq)} \rightarrow 5\text{Fe}^{3+}\text{(aq)} + \text{Mn}^{2+}\text{(aq)} + 4\text{H}_2\text{O(l)}, verify atom and charge balance.
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Background Knowledge

These ideas may be useful before you work through the harder examples.

precipitation reactiondouble displacement