Join TSR now and get all your revision questions answeredSign up now

Phosphorus hexafluoride ion: Lewis Dot and Cross diagram Watch

    • Thread Starter
    Offline

    0
    ReputationRep:
    I need to draw a Lewis dot and cross diagram for the phosphorus hexafluoride ion for my IB Chemistry HL. I tried but ended up with the phosphorus atom having 12 shared electrons with 6 fluorine atoms. But doesn't phosphorus only have 5 electrons to covalently bond with? Ahhhh.

    Help would be much appreciated

    Merry [Belated] Christmas !
    • Community Assistant
    • Study Helper
    Offline

    3
    ReputationRep:
    (Original post by fablesofgray)
    I need to draw a Lewis dot and cross diagram for the phosphorus hexafluoride ion for my IB Chemistry HL. I tried but ended up with the phosphorus atom having 12 shared electrons with 6 fluorine atoms. But doesn't phosphorus only have 5 electrons to covalently bond with? Ahhhh.

    Help would be much appreciated

    Merry [Belated] Christmas !
    Just do it one step at a time...

    Phosphorus has 5 outer electrons = 5
    Each fluorine provides 1 electron = 6
    The negative charge must be added in = 1
    -------------------------------------------------------- add together
    Total electrons around the phosphorus = 12

    This makes 6 pairs = electronically octahedral

    Each P-F bond requires 2 electrons and there are 6 P-F bonds = 12 electrons

    Hence all electrons used up in bonding. Ionic shape is also octahedral.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by charco)
    Just do it one step at a time...

    Phosphorus has 5 outer electrons = 5
    Each fluorine provides 1 electron = 6
    The negative charge must be added in = 1
    -------------------------------------------------------- add together
    Total electrons around the phosphorus = 12

    This makes 6 pairs = electronically octahedral

    Each P-F bond requires 2 electrons and there are 6 P-F bonds = 12 electrons

    Hence all electrons used up in bonding. Ionic shape is also octahedral.
    Thank you!

    Haven't learnt about VSEPRT and hybridisation yet... but will do so soon
 
 
 
Poll
Is GoT overrated?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.