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If A₂Z₃ is an ionic compound, the ions that form it would be A⁺³ and Z⁻².
The atoms that can form A⁺³ ions are in the 13th group of the periodic table, so two elements that can be A are Aluminum (Al) and Galium (Ga).
The atoms that can form Z⁻² ions are in the 16th group of the periodic table, so two elements that can be Z are Oxygen (O) and Sulfur (S).
Al₂O₃ (Aluminum Oxide) is an example of an A₂Z₃ compound
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