Precipitation Party
Mix solutions to create insoluble salt precipitates
What this lesson covers
Why it matters
Mix two clear, colourless liquids and watch them instantly turn cloudy with a solid that wasn't there before.
The idea in plain words
Trace the ions: Ag⁺ pairs with Cl⁻ to form AgCl(s). Na⁺ and NO₃⁻ remain in solution as spectator ions.
Predict first
What happens when you mix silver nitrate and sodium chloride solutions?
The ions swap partners. Silver meets chloride to form insoluble silver chloride, which drops out as a white precipitate.
- A white solid forms immediately — correct
- The solution bubbles vigorously
- Nothing happens; the solution stays clear
- The solution turns blue
What you do
Run both reactions. Note the white precipitate in the first and the formation of lead sulphate in the second. Compare the equations.
Check yourself
In the reaction AgNO₃ + NaCl → AgCl + NaNO₃, why does AgCl form a precipitate?
Solubility rules dictate that silver chloride is insoluble, so it separates from the solution as a solid.
What type of reaction is Pb(NO₃)₂ + Na₂SO₄ → PbSO₄ + 2NaNO₃?
The cations and anions of two compounds exchange partners to form two new compounds.
Which observation matches the reaction between silver nitrate and sodium chloride?
The verified data states that AgCl forms as a white precipitate in this double decomposition reaction.
- It is insoluble in water — correct
- It is a gas
- It is highly soluble
- It reacts with air
- Double decomposition — correct
- Decomposition
- Displacement
- Combination
- Formation of white AgCl precipitate — correct
- Formation of yellow precipitate
- Evolution of a colourless gas
- Solution turns red