# G-chem question----->Molecular geometry

Discussion in 'DAT Discussions' started by Imanm, 07.07.10.

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1. ### Imanm 2+ Year Member

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What is the molecular geometry of Iodine in IF4-????

3. ### Jia7 5+ Year Member

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IF4- has 5 electron domains (1 lone pair of e-'s) or sp3d hybridization. Electron domain geometry will be trigonal bipyramidal. Since it is attached to 4 atoms and has one lone pair its molecular geometry is See-saw.

4. ### Imanm 2+ Year Member

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thank you Jia.
ok great thats what I thought but the anwer key says its Octahedral so I got confused. can anyone else confirm see-saw just because I am OCDing.
Thank you

5. ### nainaaz

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hmm.. IF4- have 6 domain (4 bonded to fluorine and 2 lone pairs of e-s) total 36 es-

so it will have square planar shape specifically... or it has sp3d2 conf. so octahedral, if given will be correct answer choice also

6. ### jirotrom 5+ Year Member

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correct!

7. ### Jia7 5+ Year Member

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nainaaz is correct. I calculated incorrectly. The calculations should be 7*5 = 35 valence electrons + 1 negative charge = 36 - 8 bonded electrons = 28 - 6(4) lone pairs e-'s on the 4F's = 4 and that should give you 2 lone pair of electrons on I.

The electron domain geometry is octahedral but the molecular geometry is square planar.

8. ### Imanm 2+ Year Member

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K thank you all.

9. ### shiftypoptart 5+ Year Member

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Yup this is definitely square planar for molecular geometry and octahedral for electron domain geometry but they almost never ask for the electron domain geometry. Its always good to keep an eye out for when they do ask about either cause it is different when you have lone pairs.