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Drawing shape of ions

'draw the shape of PO4 (-3) ( the -3 is the charge on the ion)'

So can you use the shape of PO4 and add 3 electrons to your dot and cross diagram?

Reply 1

SamuelN98

Original post by indignation

'draw the shape of PO4 (-3) ( the -3 is the charge on the ion)'

So can you use the shape of PO4 and add 3 electrons to your dot and cross diagram?

If you need the shape then you don`t need to do a dot and cross diagram. As there are 4 sets of electrons around the central phosphorus it will have a tetrahedral shape with 109 degree bond angles (this is for the OCR B Salters sylabus)

Note: There will be three single bonds to oxygen and one double bond.

(edited 7 years ago)

Reply 2

indignation

Original post by SamuelN98

How did you know about the 1 double bond and 2 single?

Reply 3

AlphaWolfZ

Wouldn't be 6 pairs of electrons, 4 bonding pairs and 2 lone pairs? Here's my thought process:

1/ Outer electrons of central atom P 5
2/ Electrons brought by the Oxygens 4x1
3/ Add 3 e- due to charge 12
4/ Divide by 2 6

Therefore wouldn't be a square planar?