incomplete octet
Quick Summary
In chemistry, the octet rule states that atoms tend to combine in such a way that they each have eight electrons in their outer electron shell. This arrangement is similar to that of noble gas atoms, which are known for their stability and lack of reactivity.1
However, some compounds do not follow this rule and have an atom with fewer than eight electrons in its outer shell. These are called incomplete-octet compounds. An example is boron trifluoride (BF₃). In BF₃, the boron atom only shares six valence electrons, making it highly reactive and useful as a catalyst in chemical reactions. This incomplete octet allows the boron atom to form bonds with other atoms, facilitating chemical processes.2
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