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BF4 Structure, in terms of Bond Angles...

What is the structure of BF4, to the minus, in terms of Linear, Tetrahedral, Trigonal Planar etc...

Boron only has 3 electrons in outer shell, so how is it possible to bond 4 Flourines?

Thank you!

Reply 1

Ourkid

... BF4, to the minus,

do you mean BF4^-? because that would answer your 3 outer electron question, as the minus charge means an extra electron is present, which would provide the one electron each for each flourine. Alternatively it could be BF3, which a dative covalent bond with flourine, as opposed to the B having an extra electron. This seems more likely to me :smile:

.

The shape I would say tetrahedral as you have the four outer atoms, but the bond angles would be slightly squashed on the non datives.

I think thats right. Someone correct me if I'm wrong.

cheers
w00tt

Reply 2

Rattata

Is it trigonal pyramidal?

This shape of angles business is doing my head in!

Reply 3

Rattata

This is so embarrassing btw but what the heck, might aswell say it out load! :biggrin:

ITS OFFICIAL. I am obsessed with the way Trigonal is pronounced. The word sounds sooo posh... like some kind of a drug! yummyy. Trigonalllllll… :P

wow. i sound so stupid!

Reply 4

NathanM

Rattata

wow. i sound so stupid!

no comment :p:

Reply 5

Rattata

NathanM

no comment :p:

tyvm.

Reply 6

charco

Study Forum Helper

BF4- is tetrahedral with NO distortion. The atoms themselves make no distinction between normal covalent and dative covalent bonds. These are just ideas to help us explain where the electrons have come from. Once the molecules or ions are formed the electrons are perfectly symmetrical.