KI is an ionic compound because when the metal combines with nonmetal, it usually forms an ionic compound. Here, K (potassium) is a metal and I (iodine) is a nonmetal. So when they combine, it forms an ionic compound.
Well, now you have got to know that KI is an ionic compound, but let me explain the in-depth reason why KI is an ionic compound.
If you are a visual learner like me, then here is a short one minute video for you.
Why is KI 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 KI, the K atom is a metal and the I atom is a nonmetal.
Hence the bond between them is an ionic bond.
How does the ionic bond form between K and I?
In KI, there are two atoms;
K and I.
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 Iodine (I):
Iodine atom have 53 electrons.
The electrons arrangement in Iodine (I) is 2, 8, 18, 18, 7.
So the outermost orbit of an Iodine atom has 7 electrons.
Now Iodine 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 Iodine atom will gain 1 electron to form a stable octet.
What happens when K and I combine?
When K and I combine with each other, the electron transfer takes place from the Potassium atom to Iodine atom (i.e from K to I).
In other words, the Potassium atom (K) loses 1 electron and the Iodine atom (I) gains 1 electron.
Due to this, Potassium becomes a positive ion (K+) and Iodine becomes a negative ion (I–).
Now because of the positive charge of Potassium ion and negative charge of Iodine ion, the electrostatic force of attraction is produced between them.
This electrostatic force between Potassium ion and Iodine ion results in an ionic bond between them.
Hence, KI is an ionic compound.
I hope you have understood the reason why KI is an ionic compound.
Check out other compounds to see whether they are ionic or covalent;
Is CaCO3 Ionic or Covalent?
Is MgBr2 Ionic or Covalent?
Is LiBr Ionic or Covalent?
Is NaOH Ionic or Covalent?
Is HBr 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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