What is the name is the ionic compound CaO 1 calcium oxygen 2 calcium oxide 3 calcium (I) oxide 4 calcium (II) oxide
The Correct Answer and Explanation is:
The correct name of the ionic compound CaO is calcium oxide (option 2).
To understand this, let’s break it down:
- Calcium (Ca) is an alkaline earth metal from Group 2 of the periodic table. It typically forms Ca²⁺ ions because it loses two electrons to achieve a stable electron configuration.
- Oxygen (O) is a non-metal from Group 16 and forms O²⁻ ions when it gains two electrons to fill its outermost electron shell.
When calcium and oxygen combine, calcium donates its two electrons to oxygen, resulting in the ionic compound CaO. The Ca²⁺ ions and O²⁻ ions attract each other due to electrostatic forces and form a stable ionic bond.
Explanation of the Options:
- Option 1: Calcium Oxygen is not a correct name. This would be used in a more informal or descriptive context, but not in formal naming of ionic compounds.
- Option 3: Calcium (I) Oxide is incorrect. Calcium has a fixed charge of +2, not +1, so using “(I)” would be misleading. Ionic compounds formed by calcium do not need Roman numerals for the oxidation state, as calcium always has a +2 charge.
- Option 4: Calcium (II) Oxide is a valid name, but it is unnecessary because the (II) is redundant in this case. The oxidation state of calcium in CaO is always +2, so it’s unnecessary to specify it in the name.
In summary, calcium oxide is the standard and correct name for CaO.
