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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
  • inorganic chemistry - When to consider back bonding and when to not . . .
    You'll need to complete a few actions and gain 15 reputation points before being able to upvote Upvoting indicates when questions and answers are useful What's reputation and how do I get it? Instead, you can save this post to reference later
  • 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
  • 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
  • Is there any chemical that can destroy PTFE or Teflon?
    The $\ce {C-F}$ bond is shorter (135 pm) than the $\ce {Si-F}$ bond (160 pm) and therefore better serves to encase and protect the carbon backbone While there are some other polymers that have better mechanical or thermal properties, I am not aware of any that have better chemical resistance
  • How to avoid oxidation of Si using a sub nanometer layer
    It is shown that the native oxide growth is strongly suppressed by the existence of Si-F bonds of about 0 12 monolayers on the surface This is explained by a model in which Si-F bonds chemically stabilize the surface reactive sites such as atomic steps as supported by the result of the layer-by-layer oxidation of Si (My bolding)
  • If a molecule has both polar and ionic bonds in it, is it polar or . . .
    1) The silicon to fluoride bond is polar covalent Even though an electronegativity difference of more than 2 0 generally indicates an ionic bond, the cutoff rises as the average electronegativity of the two combining species rises For example, in sodium bromide, the electronegativity difference is only 1 9, but the average electronegativity between sodium (0 9) and bromine (2 5) is 1 7 which





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