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    Why does lower melting temperatures for silver halides than sodium halides support the fact that there is a degree off covalency in silver halides?

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    Covalent bonds give discrete molecules with relatively weak intermolecular interactions and lower melting points compared to ionic bonding leads which to a relatively strong ionic lattice you need to break to melt the compound.
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    (Original post by Kyri)
    Covalent bonds give discrete molecules with relatively weak intermolecular interactions and lower melting points compared to ionic bonding leads which to a relatively strong ionic lattice you need to break to melt the compound.
    So although covalent bonds are stronger than ionic bonds, they have weaker intermolecular forces so they have a lower melting point?
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    (Original post by rainerised)
    So although covalent bonds are stronger than ionic bonds, they have weaker intermolecular forces so they have a lower melting point?
    That is a common statement, but the issue with it is that you never deal with 'an ionic bond'. You have ionic lattices in which each ion will be interacting with many ions of opposite charge, and the overall effect is incredibly powerful. You never have the case of a single sodium ion interacting with a single chloride ion.

    If you treat both of these ions as point charges, knowing the interion distance in the lattice, some simple physics will give you the electrostatic attraction, and it wouldn't surprise me if it was weaker than a standard covalent bond such as C-C or C-H.
 
 
 
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