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    Why does hydrogen iodide have a low melting point??
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    Compared to what?
    Titanium!? Carbon Dioxide!?

    I'm just going to spurt out some chemistry at you and hope it works.

    Not relevant to your question:
    Iodine has a-lot of electrons compared to the other Halogens above it, therefore it shall have stronger Van der waal forces due to the higher Mr.

    Relevant to your question:
    However, Iodine also has more shielding than the Halogens above it, therefore the Electrostatic force of attraction between the nucleus and electrons will be weaker due to the shielding, thus giving Hydrogen Iodide a low melting point.
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    (Original post by Bulletzone)
    Compared to what?
    Titanium!? Carbon Dioxide!?

    I'm just going to spurt out some chemistry at you and hope it works.

    Not relevant to your question:
    Iodine has a-lot of electrons compared to the other Halogens above it, therefore it shall have stronger Van der waal forces due to the higher Mr.

    Relevant to your question:
    However, Iodine also has more shielding than the Halogens above it, therefore the Electrostatic force of attraction between the nucleus and electrons will be weaker due to the shielding, thus giving Hydrogen Iodide a low melting point.
    Thank you )) and it doesnt say anything about comparing it to another compound.
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    (Original post by a_m15)
    Thank you )) and it doesnt say anything about comparing it to another compound.
    Forgot to add, due to that weakened force of attraction between the nucleus and the electrons, the Covalent bond is weaker?

    No problem.
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    (Original post by Bulletzone)
    the Electrostatic force of attraction between the nucleus and electrons will be weaker
    This doesn't affect melting point.

    HI has a low MP as it has a simple molecular lattice with weak IMF.

    The difference in electronegativities is only fairly small, so the permanent dipole dipole attraction is quite small and since it has quite a few e-, the instantaneous dipole induced dipole attraction is of a similar size to the pdd. Together, they make the IMF reasonably large, but still lower than molecules with H-bonding.
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    (Original post by Pigster)
    This doesn't affect melting point.

    HI has a low MP as it has a simple molecular lattice with weak IMF.

    The difference in electronegativities is only fairly small, so the permanent dipole dipole attraction is quite small and since it has quite a few e-, the instantaneous dipole induced dipole attraction is of a similar size to the pdd. Together, they make the IMF reasonably large, but still lower than molecules with H-bonding.
    Thank you!
 
 
 
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