KCl (Potassium chloride) is an ionic compound because when the metal combines with nonmetal, it usually forms an ionic compound. Here, K is a metal and Cl is a nonmetal. So when they combine, it forms an ionic compound.
Well, now you have got to know that KCl is an ionic compound, but let me explain the in-depth reason why KCl is an ionic compound.
If you are a visual learner like me, then here is a short one minute video for you.
Why is KCl 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 KCl, the K atom is a metal and the Cl atom is a nonmetal.
Hence the bond between them is an ionic bond.
How does the ionic bond form between K and Cl?
In KCl, there are two atoms;
K and Cl.
About Potassium (K):
Potassium atom have 19 electrons.
The electrons arrangement in Potassium (K) is 2, 8, 8, 1.
So the outermost orbit of Potassium atom has 1 electron.
Now Potassium 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 Potassium atom will lose 1 electron to form a stable octet.
About Chlorine (Cl):
Chlorine atom have 17 electrons.
The electrons arrangement in Chlorine (Cl) is 2, 8, 7.
So the outermost orbit of Chlorine atom has 7 electrons.
Now Chlorine 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 Chlorine atom will gain 1 electron to form a stable octet.
What happens when K and Cl combine?
When K and Cl combine with each other, the electron transfer takes place from Potassium atom to Chlorine atom (i.e from K to Cl).
In other words, the Potassium atom (K) loses 1 electron and the Chlorine atom (Cl) gains 1 electron.
Due to this, Potassium becomes a positive ion (K+) and Chlorine becomes a negative ion (Cl–).
Now because of the positive charge of Potassium ion and negative charge of Chlorine ion, the electrostatic force of attraction is produced between them.
This electrostatic force between Potassium ion and Chlorine ion results in an ionic bond between them.
Hence, KCl is an ionic compound.
I hope you have understood the reason why KCl is an ionic compound.
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 chemistry learning platform that provides students with easily understandable explanations.
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