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IM forces-substances of increasing melting points

  1. May 4, 2012 #1
    Q.In which of the answers below are the substances listed in order of increasing melting
    a) Cl2 < CHF3 < H2O < CHCl3 < SiO2
    b) Cl2 < CHCl3 < CHF3 < H2O < SiO2
    c) Cl2 < CHF3 < CHCl3 < H2O < SiO2
    d) Cl2 < H2O < CHF3 < CHCl3 < SiO2
    e) SiO2 < H2O < CHCl3 < CHF3 < Cl2

    How can we tell the melting points of these substances by there intermolecular forces?

    ok H20 has hydrogen bonding, SiO2 has strong covalent bonds,CHF3 has dipole forces

    So how can develop a trend in melting points with the IM forces?

    Any suggestions?

    The answer is C
  2. jcsd
  3. May 5, 2012 #2
    SiO2 is a giant covalent structure - a macromolecule so it has the highest melting point
    H2O has hydrogen bonding
    Cl2 a gas has the lowest melting point as only vanderwaal ofrces exist

    I'm not sure about CHCl3 and CHF3 - i though CHF3 will have a higher MP because of hydrogen bonding
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