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# Drawing shape of ions

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1. '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?
2. (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.
3. (Original post by SamuelN98)
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.
How did you know about the 1 double bond and 2 single?
4. 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?
5. (Original post by indignation)
How did you know about the 1 double bond and 2 single?
This should help explain it.
http://terpconnect.umd.edu/~wbreslyn...for-PO43-.html

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