BaO is an ionic compound because when the metal combines with nonmetal, it usually forms an ionic compound. Here, Ba is a metal and O is a nonmetal. So when they combine, it forms an ionic compound.
Well, now you have got to know that BaO is an ionic compound, but let me explain the in-depth reason why BaO is an ionic compound.
Why is BaO an ionic compound?
As mentioned above, you can simply remember that when the metal combines with nonmetal, the bond between them is an ionic bond.
Here in BaO, the Ba atom is a metal and the O atom is a nonmetal.
Hence the bond between them is an ionic bond.
How does the ionic bond form between Ba and O?
In BaO, there are two atoms;
Ba and O.
About Barium (Ba):
Barium atom have 56 electrons.
The electron arrangement in Barium (Ba) is 2, 8, 18, 18, 8, 2.
So the outermost orbit of Barium atom has 2 electrons.
Now Barium is a metal and the metals are highly electropositive (that means they have the tendency to lose electrons and become positive ions.)
Hence during the chemical reaction, the Barium atom will lose 2 electrons to form a stable octet.
About Oxygen (O):
Oxygen atom have 8 electrons.
The electrons arrangement in Oxygen (O) is 2, 6.
So the outermost orbit of an Oxygen atom has 6 electrons.
Now Oxygen is a nonmetal and the nonmetals are highly electronegative (that means they have the tendency to gain electrons and become negative ions.)
Hence during the chemical reaction, the Oxygen atom will gain 2 electrons to form a stable octet.
What happens when Ba and O combine?
When Ba and O combine with each other, the electron transfer takes place from Barium atom to Oxygen atom (i.e from Ba to O).
In other words, the Barium atom (Ba) loses 2 electrons and the Oxygen atom (O) gains 2 electrons.
Due to this, Barium becomes a positive ion (Ba2+) and Oxygen becomes a negative ion (O2-).
Now because of the positive charge of Barium ion and negative charge of Oxygen ion, the electrostatic force of attraction is produced between them.
This electrostatic force between Barium ion and Oxygen ion results in an ionic bond between them.
Hence, BaO is an ionic compound.
I hope you have understood the reason why BaO is an ionic compound.
Check out other compounds to see whether they are ionic or covalent;
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Is CaSO4 Ionic or Covalent?
Is Sodium iodide (NaI) Ionic or Covalent?
Is CsF Ionic or Covalent?
Jay is an educator and has helped more than 100,000 students in their studies by providing simple and easy explanations on different science-related topics. With a desire to make learning accessible for everyone, he founded Knords Learning, an online learning platform that provides students with easily understandable explanations.
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