Metal Aqua Ions in Aqueous Solution Quiz

Metal Aqua Ions in Aqueous Solution

• Metal ions in water are surrounded by water molecules, forming hydrated ions.
• Four key metal aqua ions are: iron(II), copper(II), iron(III), and aluminium.
• These ions form coloured precipitates when reacted with various reagents.
• The metal aqua ions act as acids due to their ability to donate protons.

Acidic Properties

• Metal ions forming 2+ ions, such as iron(II) and copper(II), are weaker acids than those forming 3+ ions, like iron(III) and aluminium.
• 3+ ions dissociate more, resulting in a stronger attraction to basic OH- ions.

Reactions with NaOH

• Metal aqua ions react with sodium hydroxide (NaOH) in a neutralisation reaction, forming a salt and water.
• Precipitates formed in these reactions have colours:
  • Aluminium: white
  • Iron(II): green
  • Copper(II): blue
  • Iron(III): brown
• The number of OH- ions in the precipitate's formula matches the charge on the metal ion.

Amphoteric Salts

• Aluminium salts are amphoteric, meaning they can act as both acids and bases.
• When excess NaOH is added to aluminium salts, the salt acts as an acid and is further hydrolysed.

Reactions with Ammonia (NH3)

• Metal aqua ions react with aqueous ammonia (NH3), forming a salt and ammonium ions.
• Excess ammonia causes ligand substitution in the copper(II) precipitate, forming a deep blue solution.

Reactions with Na2CO3

• Metal 2+ ions react with sodium carbonate (Na2CO3) as acids, producing insoluble carbonates and water.
• 3+ metal ions react more strongly as acids, producing salt, water, and carbon dioxide.

Reactions with Chloride Ions (Cl-)

• All metal aqua ions undergo ligand substitution in concentrated hydrochloric acid, forming tetrahedral ions with four Cl- ligands.

Test your knowledge on metal aqua ions and their properties in aqueous solutions. This quiz covers the acidic behavior of metal ions, their reactions with sodium hydroxide, and the colors of the precipitates formed. Delve into the fascinating interactions between metal ions and water!