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[an1423]

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mY TEST IS ON TUES AND NEED A LIL HELP. iS THE STRONGEST ACID THE BULKIES OR MOST ELECTRONEGATIVE EX) HF OR HI???

ALSO, ARE HALIDES LIKE CL F ETC.... META DIRESCTOR OT O/P??? CONFUSING???? IF YOU ALSO HAVE ANY OTHER ADVICE THAT HELPED YOU OR WISH YOU KNEW BE4 THE DAT, PLEASE HELP OUT. THANKS

 

[JBarr29]

dont think in terms of bulky, or electronegative. acids are very tricky when talking about trends, especially when going up or down a column on the periodic table. Bond strength plays a significant role in determinging the strength of an acid. HI is much more acidic, because the bond strength is weaker than that of HF. HF will not want to donate its H+ because it has such a high electronegativity. HI is alot bigger, therefore has less of a bondstrength

Halides are electron withdrawing groups, but direct ortho para

 

[heatwheat]

mY TEST IS ON TUES AND NEED A LIL HELP. iS THE STRONGEST ACID THE BULKIES OR MOST ELECTRONEGATIVE EX) HF OR HI???

ALSO, ARE HALIDES LIKE CL F ETC.... META DIRESCTOR OT O/P??? CONFUSING???? IF YOU ALSO HAVE ANY OTHER ADVICE THAT HELPED YOU OR WISH YOU KNEW BE4 THE DAT, PLEASE HELP OUT. THANKS

The stronger acid is HI. I am not really good at O-Chem, but I think it has something to do with the size of the molecule. Someone else should clarify this.

Also, halides are O/P directors. They are actually DEACTIVATING, but they are still O/P directors.

Let us know how you do.

 

[dmd4u]

I think the more acidic organic molecules are the ones that are deactivating benzene rings. Not sure about other requirements.

 

[Tina324]

HI is also more acidic because I is bigger than F..which not only makes the H-I bond longer and therefore weaker, but ALSO, when the H leaves...the negative chrage on the I is better delocalized.

So i think we mainly have to look at bond length/strength and size of the ion H leaves behind.

 

[JBarr29]

yup thats all correct except the benzene ring thing doesnt apply here. but electron withdrawing groups like -NO2 make benzenes more acidic as a side note

 

[Danny289]

mY TEST IS ON TUES AND NEED A LIL HELP. iS THE STRONGEST ACID THE BULKIES OR MOST ELECTRONEGATIVE EX) HF OR HI???

ALSO, ARE HALIDES LIKE CL F ETC.... META DIRESCTOR OT O/P??? CONFUSING???? IF YOU ALSO HAVE ANY OTHER ADVICE THAT HELPED YOU OR WISH YOU KNEW BE4 THE DAT, PLEASE HELP OUT. THANKS

when you are thinking about acidity of two or more componds. compare the conjugate base. stronger acid gives you weaker conjugate base and weaker acid gives you stronger conjugate base lets try HI and HF:
HI--------> H+ + I-
HF--------> H+ + F-
now compare I- and F- which one is stronger Base?
F- is stronger base because it is more electronegative and accept proton better than I-....
hope it helped