Ionic Equations

• What is an ion?

  A charged particle
• What is an ionic compound?

  A compound formed from ions
• How does a sodium ion Na⁺ form?

  By losing one electron
• How does a chloride ion Cl⁻ form?

  By gaining one electron
• What is reduction?

  Gain of electrons
• What is oxidation?

  Loss of electrons
• Write an ionic equation for the reduction of an oxygen atom to an oxide ion.


  O + 2e⁻ → O²⁻
• Write an ionic equation for the oxidation of a calcium atom to a calcium ion.

  Ca → Ca²⁺ + 2e⁻
• Write a balanced symbol equation for the reaction between sodium hydroxide and hydrochloric acid.

  NaOH + HCl → NaCl + H₂O
• Which ion makes a solution acidic?

  H⁺ ion
• What is the formula of a hydroxide ion?

  OH⁻
• Write the ionic equation for a neutralisation reaction.

  H⁺(aq) + OH⁻(aq) → H₂O(l)
• What do you expect to see in the reaction of magnesium metal with hydrochloric acid?

  Bubbles of hydrogen gas
• What are spectators in a chemical reaction?

  Particles that do not change during the reaction
• What is the formula for lead nitrate?

  Pb(NO₃)₂
• What do ionic equations show?

  • Only the reacting particles
  • Spectator ions are not included
• What must balance in an ionic equation?

  • Charges must balance
  • Atoms must balance
• Write an ionic equation for the reaction of sodium hydroxide with hydrochloric acid.

  OH⁻(aq) + H⁺(aq) → H₂O(l)
• Write an ionic equation for the reaction of potassium hydroxide with nitric acid.

  OH⁻(aq) + H⁺(aq) → H₂O(l)
• Write a balanced symbol equation for the reaction of lead nitrate with iodide solution.

  Pb(NO₃)₂ + 2KI → PbI₂ + 2KNO₃
• Write an ionic equation for the reaction of magnesium metal with copper sulfate.

  Mg + Cu²⁺ → Mg²⁺ + Cu
• Write an ionic equation for the reaction of zinc with iron nitrate.

  Zn + Fe²⁺ → Zn²⁺ + Fe
• Write a balanced symbol equation for the reaction of sodium chloride with lead nitrate.

  2NaCl + Pb(NO₃)₂ → PbCl₂ + 2NaNO₃
• Write an ionic equation for the reaction of sodium chloride with copper nitrate.

  Cl⁻ + Cu²⁺ → CuCl₂
• Write a balanced symbol equation for the reaction of potassium hydroxide with sulfuric acid.

  2KOH + H₂SO₄ → K₂SO₄ + 2H₂O
• Write a balanced symbol equation for the reaction of sodium sulfate with lead nitrate.

  Na₂SO₄ + Pb(NO₃)₂ → PbSO₄ + 2NaNO₃
• Write an overall and ionic equation for the reaction of calcium carbonate with sulfuric acid.

  CaCO₃ + H₂SO₄ → CaSO₄ + CO₂ + H₂O; CaCO₃ + 2H⁺ → Ca²⁺ + CO₂ + H₂O
• Write a balanced symbol equation for the reaction of sodium iodide with lead nitrate.

  2NaI + Pb(NO₃)₂ → PbI₂ + 2NaNO₃
• Write an ionic equation for the reaction of sodium iodide with copper nitrate.

  I⁻ + Cu²⁺ → CuI
• Write a balanced symbol equation for the reaction of sodium sulfate with barium nitrate.

  Na₂SO₄ + Ba(NO₃)₂ → BaSO₄ + 2NaNO₃
• Write an overall and ionic equation for the reaction of hydrochloric acid with calcium hydroxide.

  2HCl + Ca(OH)₂ → CaCl₂ + 2H₂O; 2H⁺ + Ca(OH)₂ → Ca²⁺ + 2H₂O
• Write an overall and ionic equation for the reaction of sodium carbonate with sulfuric acid.

  Na₂CO₃ + H₂SO₄ → Na₂SO₄ + CO₂ + H₂O; Na₂CO₃ + 2H⁺ → 2Na⁺ + CO₂ + H₂O
• What are the general solubility rules for salts?

  • All sodium, potassium, and ammonium salts are soluble
  • All nitrates are soluble
  • Most chlorides, bromides, and iodides are soluble, except silver and lead
  • Most sulfates are soluble, except lead, barium, and calcium
  • Sodium, potassium, and ammonium carbonates are soluble; most other carbonates are not
  • Sodium and potassium hydroxides are soluble; most other hydroxides are not
  • Calcium hydroxide is slightly soluble
• What is a precipitate?

  A solid formed when two solutions mix
• What should you do to predict if an insoluble salt will form when mixing two liquids?

  Use solubility rules to predict
• What should you do after mixing solutions to complete the table with observations?

  Record your observations and compare predictions
• What should you include in your full equation for reactions that occurred?

  State symbols in your symbol equation