The Chemical bond
Explaining chemical bonding
The Octet rule- Part II
Most of the elements don't have a full shell of electrons (octet) as the noble gases do. They will have to interact with other elements in order to achieve the ideal situation, which is to have 8 electrons in the valence (outer) shell.
Let's look at these examples below , Na (11 electrons) on the left side and F (9 electrons) on the right:
It has been shown in ionic bonds that Na donates an electron to Cl, so that they become Na+ and Cl- respectively and end up being attracted to each other electrostatically, forming a bond.
Based on the images above, it will be explained now how the Na-F bond is formed (F has a chemical behaviour similar to Cl and that will be understood very soon).
Na has 1 electron alone on the valence shell. It can achieve the octet by losing this electron, because this way the 2nd shell which contains 8 electrons would become the valence shell.
It still need something to take that electron away, otherwise it cannot lose it. That is where F comes into play. F has 7 electrons in its valence shell, so that it needs to receive 1 to achieve the octet .
So that is it! Na passes its outer electron to F and both end up with 8 electrons in the valence shell!
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