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- inorganic chemistry - Why is the Si-F bond one of the strongest single . . .
I honestly have no clue where to begin explaining why the Si-F bond is one of the strongest single covalent bonds of them all I would actually predict the bond to be relatively weak on account of the relatively large size of the Si atom leading to a relatively long bond length and hence poor orbital overlap
- Reaction of Silicon Dioxide with Hydrofluoric Acid
If you are using comparative bond strengths to determine if a reaction is favorable, you need to consider the bonds in the products as well as those in the reactants Although H-F has a stronger bond than H-Cl and other halogen acids, the Si-F bond is one of the strongest single bonds known, so forming four of them in the product makes the reaction thermodynamically favorable Si-Cl bonds are
- Why is covalent bonding stronger than electrostatic attraction?
The article by Gillespie argues you should avoid the phrase "ionic character" because "ionic" and "covalent" aren't mutually exclusive It's pretty clear from dipole moment in diatomic LiF and quantum calculations that ~0 9 electrons are transferred OTOH, B-F and Si-F clearly have both shared electron density AND electrostatic contributions, so both are important in the bonding in these
- Why do non-metals not form Ionic bonds (Ti-C, Sc-P) and instead form . . .
As Poutnik describes in his answer, low-electronegativity nonmetallic such as boron form bonds with low ionic character because in general, their atoms are not strongly electronegative enough to fully withdraw electrons even from highly electropositive metals (which still do require some ionization energy) Nonetheless, incorporating such atoms into structures whose molecular orbitals are more
- inorganic chemistry - When to consider back bonding and when to not . . .
$\mathrm p$ π- $\mathrm d$ π bonding is very weak and normally not considered to be very effective in bonding Rather, the bonding can be explained via ionic bonding instead due to the large electronegativity differences This can be seen in siloxanes and trisilylamine According to J Am Chem Soc 1980, 102 (24), 7241–7244 Since our ab initio calculations reproduce the geometry and
- organic chemistry - Why is the carbon-fluorine bond stronger than the . . .
From wikipedia article of carbon-fluorine bond, The high electronegativity of fluorine (4 0 for F vs 2 5 for carbon) gives the carbon–fluorine bond a significant polarity dipole moment The electron density is concentrated around the fluorine, leaving the carbon relatively electron poor This introduces ionic character to the bond through partial charges ($\ce {C^ {δ+}—F^ {δ−}}$) The
- How much can we extend the Finkelstein reaction?
They need something like a silane to activate them because the Si–F bond is of a competitive strength Yes, the Finkelstein can work in other solvents, especially with the correct activators You can even do the Finkelstein on aromatic rings if you add catalytic copper (I) iodide and a diamine to activate it
- halides - Why is fluorine more reactive than iodine despite the weaker . . .
Silica is readily attacked by $\ce {HF}$ not because it is a strong acid, but rather because of the strength of $\ce {Si-F}$ bond thus formed That deals with the thermodynamic parts of "reactivity", in the sense that it explains why some reactions with iodine require elevated temperatures for any significant conversion, whereas reactions with
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