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Net Ionic Equation Calculator

Enter a molecular equation, for example a precipitation or neutralisation reaction. The calculator balances it, splits strong electrolytes into ions using the solubility rules, and cancels the spectator ions to leave the net ionic equation.

Quick answer: for AgNO3 + NaCl → AgCl + NaNO3 the net ionic equation is Ag+(aq) + Cl−(aq) → AgCl(s). Na+ and NO3− are spectator ions.
Results appear here.

Add states such as CaCO3(s) to override the solubility rules. Only common inorganic acids, bases and salts are recognised. Check unusual compounds yourself.

How to use the net ionic equation calculator

  1. Enter the molecular equation with ordinary formulas: BaCl2 + Na2SO4 = BaSO4 + NaCl. It does not need to be balanced.
  2. The tool balances it, then decides for each compound whether it dissolves as ions (strong acids, strong bases, soluble salts) or stays together (precipitates, gases, water, weak acids, metals).
  3. It writes the complete ionic equation and cancels ions that appear unchanged on both sides (the spectator ions).
  4. Read the net ionic equation. Expand Why each species was split to see which solubility rule was applied.

Worked examples

Precipitation: lead(II) iodide

Pb(NO3)2 + 2 KI → PbI2 + 2 KNO3

Pb2+(aq) + 2 I−(aq) → PbI2(s)

Spectators: K+, NO3−

Neutralisation

HCl + NaOH → NaCl + H2O

H+(aq) + OH−(aq) → H2O(l)

Gas-forming: carbonate + acid

Na2CO3 + 2 HCl → 2 NaCl + H2O + CO2

CO32−(aq) + 2 H+(aq) → H2O(l) + CO2(g)

Molecular, complete ionic and net ionic equations

A molecular equation shows complete formulas. The complete ionic equation writes every strong electrolyte dissolved in water as separate ions. Ions that appear unchanged on both sides are spectator ions. Removing them leaves the net ionic equation, which shows the chemistry that actually happens.

Solubility rules used

Usually soluble (split into ions)Exceptions (stay solid)
Group 1 (Li+, Na+, K+…) and NH4+ saltsnone
Nitrates, acetates, perchlorates, chloratesnone
Chlorides, bromides, iodidesAg+, Pb2+, Hg22+, Cu+
SulfatesBa2+, Sr2+, Pb2+, Ca2+, Ag+, Hg22+
Usually insoluble (stay solid)Exceptions (soluble)
HydroxidesGroup 1, Ba2+, Sr2+, Ca2+ (moderately)
Carbonates, phosphates, sulfides, sulfites, chromates, oxalates, oxidesGroup 1 and NH4+

Strong acids (HCl, HBr, HI, HNO3, H2SO4, HClO4, HClO3) are split into ions. Weak acids such as CH3COOH and HF, plus water, gases and metals, stay as written.

Limitations. The rules are the standard general-chemistry simplifications. Slightly soluble salts (CaSO4, Ca(OH)2), H2SO4's second dissociation, complex ions and organic salts are simplified. If you know a state, type it (e.g. CaSO4(aq)) and the tool will follow it.

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Frequently asked questions

How do you write a net ionic equation?

Balance the molecular equation, split all soluble strong electrolytes into ions, then cancel ions that appear unchanged on both sides. What remains is the net ionic equation.

What are spectator ions?

Ions that are present in the solution but do not take part in the reaction. They appear identically on both sides of the complete ionic equation, for example Na+ and NO3- in AgNO3 + NaCl.

Which compounds are split into ions?

Strong acids, strong bases and soluble ionic salts in aqueous solution. Solids (precipitates), liquids such as water, gases, weak acids and weak bases, and metals are kept as complete formulas.

What if there is no net ionic equation?

If every ion is a spectator, for example NaCl + KNO3, no precipitate, gas or water forms and there is no net reaction.

Is the net ionic equation for every strong acid + strong base the same?

Yes. For any strong acid with a strong hydroxide base that forms a soluble salt, the net ionic equation is H+(aq) + OH-(aq) → H2O(l).

Does the calculator know every compound's solubility?

No. It applies the standard solubility rules for common ions and flags compounds it is unsure about. Add a state symbol to override it.

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