Solubility Skills

Writing Formulas

100

Write the formula for carbon dioxide.

CO₂

200

Write the formula for magnesium chloride.

MgCl₂

300

Write the formula for calcium carbonate.

CaCO₃

400

Write the formula for iron(III) sulfate.

Fe₂(SO₄)₃

500

Write the formula for ammonium phosphate.

(NH₄)₃PO₄

Solubility Rules

100

Is sodium chloride (NaCl) soluble or insoluble?

Soluble (all Group 1 compounds are soluble)

200

Is silver nitrate (AgNO₃) soluble or insoluble?

Soluble (all nitrates are soluble, no exceptions)

300

Is barium hydroxide (Ba(OH)₂) soluble or insoluble?

Soluble (hydroxides are insoluble EXCEPT Group 1, Ba, Sr — Ca is slightly soluble)

400

Is lead(II) sulfate (PbSO₄) soluble or insoluble?

Insoluble (sulfates are soluble except Ba, Pb, Ca, Sr, Ag)

500

Sodium carbonate solution is mixed with calcium chloride solution. Which product (if either) will precipitate?

Calcium carbonate (CaCO₃) — carbonates are insoluble except Group 1/NH₄⁺; sodium chloride formed stays dissolved.

Word Equation to skeleton formula

100

Sodium chloride + silver nitrate → silver chloride + sodium nitrate. Write the skeleton equation.

NaCl + AgNO₃ → AgCl + NaNO₃

200

Potassium iodide + lead(II) nitrate → lead(II) iodide + potassium nitrate. Write the skeleton equation.

KI + Pb(NO₃)₂ → PbI₂ + KNO₃

300

Barium chloride + sodium sulfate → barium sulfate + sodium chloride. Write the skeleton equation.

BaCl₂ + Na₂SO₄ → BaSO₄ + NaCl

400

Iron(III) chloride + sodium hydroxide → iron(III) hydroxide + sodium chloride. Write the skeleton equation.

FeCl₃ + NaOH → Fe(OH)₃ + NaCl

500

Ammonium sulfate + barium nitrate → barium sulfate + ammonium nitrate. Write the skeleton equation.

(NH₄)₂SO₄ + Ba(NO₃)₂ → BaSO₄ + NH₄NO₃

Balancing Equations

100

NaCl + AgNO₃ → AgCl + NaNO₃

already balanced

200

KI + Pb(NO₃)₂ → PbI₂ + KNO₃

2KI + Pb(NO₃)₂ → PbI₂ + 2KNO₃

300

BaCl₂ + Na₂SO₄ → BaSO₄ + NaCl

BaCl₂ + Na₂SO₄ → BaSO₄ + 2NaCl

400

FeCl₃ + NaOH → Fe(OH)₃ + NaCl

FeCl₃ + 3NaOH → Fe(OH)₃ + 3NaCl

500

Balance: Al₂(SO₄)₃ + BaCl₂ → BaSO₄ + AlCl₃

Al₂(SO₄)₃ + 3BaCl₂ → 3BaSO₄ + 2AlCl₃

State symbol and full equations

100

Add state symbols: NaCl + AgNO₃ → AgCl + NaNO₃

NaCl(aq) + AgNO₃(aq) → AgCl(s) + NaNO₃(aq)

200

Potassium iodide reacts with lead(II) nitrate. Write the full balanced equation with states.

2KI(aq) + Pb(NO₃)₂(aq) → PbI₂(s) + 2KNO₃(aq)

300

Barium chloride reacts with sodium sulfate. Write the full balanced equation with states.

BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq)

400

Sodium chloride solution is mixed with potassium nitrate solution. Write the full equation with states, or explain why none is needed.

No reaction — both possible products (NaNO₃ and KCl) are soluble, so no precipitate forms.

500

Iron(III) chloride reacts with sodium hydroxide. Write the complete balanced equation with correct state symbols.

FeCl₃(aq) + 3NaOH(aq) → Fe(OH)₃(s) + 3NaCl(aq)