KCl Lewis formula

Fiona Grant 1I
Posts: 30
Joined: Fri Apr 06, 2018 11:03 am

KCl Lewis formula

In one of the first lectures of this unit, we did an example of the Lewis formula of KCl. In this example, Cl ended up with all of the electrons in the final Lewis structure. I was just wondering why this was the case? How often would we have to do this type of Lewis structure rather than what we have been doing in class more recently?

Natalie Noble 1G
Posts: 30
Joined: Thu Feb 01, 2018 3:02 am
Been upvoted: 1 time

Re: KCl Lewis formula

This is because it is an ionic bond. Ionic bonds form between metals and nonmetals. In this case, K is the metal and Cl is the nonmetal. To form an octet, K gives up an electron to give to Cl, so now Cl has 8 electrons and gains stability. The reason K is so willing to give up the electron is because in order for it to have an octet and become stable it needs to lose an electron. (Ionic bonds are with cations(K) and anions(Cl). This is only the case between a metal and a nonmetal. Covalent bonds are two nonmetals sharing electrons. To the second part of your question, I don’t know if we are expected to make a formula like this but I would assume so.

Enzo_1I
Posts: 19
Joined: Fri Apr 06, 2018 11:02 am

Re: KCl Lewis formula

Because when K and Cl bond, an Ionic bond forms. K will transfers its valence electrons to Cl. If it was a covalent bond, they would share electrons.

fara valdez
Posts: 48
Joined: Fri Apr 06, 2018 11:05 am

Re: KCl Lewis formula

This is a bit confusing. How would you exactly know, every time you conduct a lewis structure diagram, which element gives/receives, or when they share?

204750609
Posts: 18
Joined: Fri Apr 06, 2018 11:02 am

Re: KCl Lewis formula

A way in which you can evaluate which gives or receives is when you evaluate the element on its own, in this case Cl has a higher ionization energy than K, so it is more likely/easier for Cl to receive an electron to satisfy the octet rule than K

Enzo_1I
Posts: 19
Joined: Fri Apr 06, 2018 11:02 am

Re: KCl Lewis formula

To determine if they share electrons, you could look at the periodic table and see if your compound is made up of two nonmetals. If it is then it shares electrons, since covalent bonds occurs with non metallic atoms.

SamanthaGrohe1B
Posts: 31
Joined: Fri Apr 06, 2018 11:03 am

Re: KCl Lewis formula

You can also observe the electronegativity trends of the periodic table with those elements that have the highest attraction for electrons being in the top right corner of the table and those elements that are the most likely to lose electrons within a bond being in the bottom left corner.