Why are complex ions readily formed when water molecules react with the cation but not with the hydronium ions ?

Explanation

To answer the question of why complex ions are readily formed when water molecules react with cations but not with hydronium ions, we can break down the explanation into a few clear steps:

### Step 1: Understanding Complex Ions
Complex ions are formed when a central metal cation binds with one or more ligands. Ligands are molecules or ions that can donate a pair of electrons to the metal cation.

### Step 2: Role of Water as a Ligand
Water (H₂O) is a common ligand due to its ability to donate a lone pair of electrons. Each water molecule has two lone pairs of electrons, and it can act as a Lewis base by donating one of these pairs to a metal cation.

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