Divalent Cations:

* Definition: A divalent cation is an ion with a +2 charge. This means it has lost two electrons.

* Common Examples:

* Alkaline Earth Metals (Group 2): These elements readily lose two electrons to form +2 ions. Examples include:

* Beryllium (Be²⁺)

* Magnesium (Mg²⁺)

* Calcium (Ca²⁺)

* Strontium (Sr²⁺)

* Barium (Ba²⁺)

* Transition Metals: Many transition metals can form divalent cations, often with multiple oxidation states. Examples include:

* Iron (Fe²⁺)

* Copper (Cu²⁺)

* Zinc (Zn²⁺)

* Nickel (Ni²⁺)

* Cobalt (Co²⁺)

* Other Metals: Some other metals can also form divalent cations, such as:

* Lead (Pb²⁺)

* Tin (Sn²⁺)

* Mercury (Hg²⁺)

Trivalent Anions:

* Definition: A trivalent anion is an ion with a -3 charge. This means it has gained three electrons.

* Common Examples:

* Nonmetals: Trivalent anions are typically formed by nonmetals in groups 15 and 16. Examples include:

* Nitrogen (N³⁻) - Nitride ion

* Phosphorus (P³⁻) - Phosphide ion

* Arsenic (As³⁻) - Arsenide ion

* Antimony (Sb³⁻) - Antimonide ion

* Polyatomic Anions: Some polyatomic ions can also have a -3 charge, such as:

* Phosphate (PO₄³⁻)

* Arsenate (AsO₄³⁻)

Important Note:

* The formation of divalent cations and trivalent anions depends on the specific element's electron configuration and its tendency to gain or lose electrons to achieve a stable octet.

Let me know if you'd like more detail on any specific element or ion!