CsF is an ionic compound because when the metal combines with nonmetal, it usually forms an ionic compound. Here, Cs (cesium) is a metal and F (fluorine) is a nonmetal. So when they combine, it forms an ionic compound.
Well, now you have got to know that CsF is an ionic compound, but let me explain the in-depth reason why CsF is an ionic compound.
If you are a visual learner like me, then here is a short one minute video for you.
Why is CsF 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 CsF, the Cs atom is a metal and the F atom is a nonmetal.
Hence the bond between them is an ionic bond.
How does the ionic bond form between Cs and F?
In CsF, there are two atoms;
Cs and F.
About Cesium (Cs):
Cesium atom have 55 electrons.
The electrons arrangement in Cesium (Cs) is 2, 8, 18, 18, 8, 1.
So the outermost orbit of a Cesium atom has 1 electron.
Now Cesium 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 Cesium atom will lose 1 electron to form a stable octet.
About Fluorine (F):
Fluorine atom have 9 electrons.
The electrons arrangement in Fluorine (F) is 2, 7.
So the outermost orbit of Fluorine atom has 7 electrons.
Now Fluorine 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 Fluorine atom will gain 1 electron to form a stable octet.
What happens when Cs and F combine?
When Cs and F combine with each other, the electron transfer takes place from Cesium atom to Fluorine atom (i.e from Cs to F).
In other words, the Cesium atom (Cs) loses 1 electron and the Fluorine atom (F) gains 1 electron.
Due to this, Cesium becomes a positive ion (Cs+) and Fluorine becomes a negative ion (F–).
Now because of the positive charge of Cesium ion and negative charge of Fluorine ion, the electrostatic force of attraction is produced between them.
This electrostatic force between Cesium ion and Fluorine ion results in an ionic bond between them.
Hence, CsF is an ionic compound.
I hope you have understood the reason why CsF is an ionic compound.
Check out other compounds to see whether they are ionic or covalent;
Is KF Ionic or Covalent?
Is KOH Ionic or Covalent?
Is PF3 Ionic or Covalent?
Is PBr3 Ionic or Covalent?
Is SrCl2 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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