Textbook Q 2F #7

[Marco Morales 2G]

The question states:

" Identify the hybrid orbitals used by the atom in boldface red type in each of the following species: b) AsF3"

the back of the book says the answer is sp^3. Can someone explain how they got the answer? Please! Thank you!

[abby hyman]

Hey! So AsF3 has a tetrahedral arrangement but a pyramidal shape due to the fourth electron region being a lone pair rather than an atom. The tetrahedral arrangement means that there is a hybridization of the one S and three P orbitals which is why it is sp3. You can also think of it as s + p*p*p.

[Lea Baskin Monk 1F]

AsF3 has a trigonal pyramidal shape but a tetrahedral electron density organization (because there is a lone pair on the As). That means there are 4 areas of electron density in this molecule (3 bonds with the F atoms and 1 lone pair). 4 areas of electron density means we need 1 s orbital and 3 p orbitals which is sp^3 hybridization.

[TJ Lai 2H]

Here's how I drew the Lewis structure. The lone pair, as well as the bonding pairs, all "count" with regards to hybridization, so in this case AsF3 has 4 groups that count towards hybridization -> sp3

Here's a really quick and helpful video that I've used that explains this concept really well: https://www.youtube.com/watch?v=4xl0BD-tMeA

[Lea Chamoun 2J]

The As atom in AsF3 has sp3 hybridization because it is surrounded by 4 regions of electron density- 3 bonding pairs and 1 lone pair. This means there is a total of 4 hybridized orbitals, which is given by sp3.