Give two examples of trivalent metal ions.

Explanation

To answer the question "Give two examples of trivalent metal ions," we can follow these steps:

### Step 1: Understand the Definition of Trivalent Metal Ions
Trivalent metal ions are metal ions that have three valence electrons and can form positively charged cations with a charge of +3.

### Step 2: Identify Groups of Metals
Trivalent metal ions are often found in specific groups of the periodic table. For example, metals in Group 13 typically exhibit trivalence.

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