[lregnidemvopthyjbfdzckdej]

Is there any table to ionic bond energy and length somewhere? I found just covalent table.
For example: how many H2O needed to break an NaCl? By the way: what is the attraction strength of a bipolar molecule like H2O?

[magician4]

Is there any table to ionic bond energy and length somewhere? I found just covalent table.

bond length and bond energy don't correlate well with "ionic" substances

one of the reasons is, that even for the most extreme example for "ionic" bonds - lithiumfluoride LiF - you still have additional like ~ 40% covalent bond not related to distance of charges  (this distance being the only source of energy release for theoretically "pure" ionic bonds)

hence, such a table would be of little use in my opinion

For example: how many H2O needed to break an NaCl?

twelve, if memory serves, in the first line of hydratisation
however, if you look at the data for a saturated NaCl solution at 20°C, 9 might be sufficient, too
... but that's somewhat debateable, as this wouldn't be a solution of ions in water, but in solvatized ions instead

what is the attraction strength of a bipolar molecule like H2O?

this depends on the question from which side your monopole will come, and how far it is away.
the rest is pure physics: calculation of the force between a monopole and a dipole of known dipole momentum


regards

Ingo

[Borek]

even for the most extreme example for "ionic" bonds - lithiumfluoride LiF

CsF

[magician4]

@ Borek:

CsF has a greater electronegativity difference, I agree

however, I didn't refer to this, but to "% ionic character" of the bond instead.
for this value, bond length nucleus - nucleus comes into picture  ( as this will influence the energy release from charges approach, with the reciprocal square of distance)

... and thats where the huge Cs spoils the party for CsF, and LiF will win

regards

Ingo

[Borek]

I have checked my General Chemistry book and did some googling and it looks like this is rather murky water. There is a definition of % ionic character based on the measured dipole moment (which - according to my GenChem book - is only approximate), plus there are several definitions (or calculation methods) that are based on the electronegativity differences - and that ignore the bond length at all.

Do you know what the ultimate definition is? So far it looks like a rather handwavy concept.

[magician4]

I know that there's a lot of debateable stuff around with "% ionic character" ( as almost always when it comes to "ions") , and I esp. am very uncomfortable with everything subsequently based on "electronegativity" (as this is another such debateable concept in it's own right, which, in total, due to the law of error propagation in my understanding squares the murkiness)

Therefore, though I don't know if it's the official / binding definition, I prefer  the comparison of theoretically calculated dipolemoment of a dipole with a distance r between the charges, and the for-real measured value for named dipolemoment of the real molecule - whenever I am forced to use this abstract concept at all.


regards

Ingo