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    how do you know which bond a compound has by seeing it.
    for example:

    Chlorine, Cl2, is a gas at room temperature whereas bromine, Br2, is a liquid under the same
    conditions.
    Explain these observations.

    the ans: fewer electrons in Cl 2 than in Br2 ora (1)
    weaker van der Waals’ forces in Cl 2 or stronger van der Waals’ forces in Br2 (1)


    or

    The gases nitrogen, N2, and carbon monoxide, CO, are isoelectronic, that is they have the
    same number of electrons in their molecules.
    Suggest why N2 has a lower boiling point than CO.

    the ans: CO has a permanent dipole or N2 does not (1)
    permanent dipole-permanent dipole interactions are stronger than those from induced
    dipoles 1


    so how am i supposed to understand by seeing the compound that it has this bonds or this intermolecular forces

    would appreciate ur help
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    (Original post by sanjukp)
    how do you know which bond a compound has by seeing it.
    for example:

    Chlorine, Cl2, is a gas at room temperature whereas bromine, Br2, is a liquid under the same
    conditions.
    Explain these observations.

    the ans: fewer electrons in Cl 2 than in Br2 ora (1)
    weaker van der Waals’ forces in Cl 2 or stronger van der Waals’ forces in Br2 (1)


    or

    The gases nitrogen, N2, and carbon monoxide, CO, are isoelectronic, that is they have the
    same number of electrons in their molecules.
    Suggest why N2 has a lower boiling point than CO.

    the ans: CO has a permanent dipole or N2 does not (1)
    permanent dipole-permanent dipole interactions are stronger than those from induced
    dipoles 1


    so how am i supposed to understand by seeing the compound that it has this bonds or this intermolecular forces

    would appreciate ur help
    For As levels you should know that inter-molecular forces are slightly broken in a liquid and almost completely for a gas. Hence when 2 substances have different forms in the same condition you must refer to either the type or the strength of inter-molecular forces that are present.
    Hydrogen bonding > permanent dipole> London forces.
    Also London forces depends on both the number of electrons and the size of the molecule, an increase in either leads to an increase in London forces.
    ex boiling points of alkanes increase as chain length increase.
    Hope this helps
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    yup got this

    can u also help me out with identifying the bonds in a compound for example when i see any compound how should i understand that it has this type of bond.

    actually i missed classes for these chaps nd i never understood them
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    (Original post by sanjukp)
    yup got this

    can u also help me out with identifying the bonds in a compound for example when i see any compound how should i understand that it has this type of bond.

    actually i missed classes for these chaps nd i never understood them
    This depends on elctronegativity, how much an atom in a compound attracts the electrons in a covelant bond.
    ex Cl-Cl both attract the bonded electrons the same

    H-Cl the Cl will attract the bonded electrons more and so Cl will be slightly negative and H will be slightly positive. So one side will be negative and one will be positive,and the opposite ends of different molecules attract each other and so stronger inter-molecular forces.
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    yeah bt I meant like how do i know that it has hydrogen bonds or does it have permanent dipoles or does it have van der Waals
    like in my example it says CO has a permanent dipole or N2 does not, so how do I know that CO has permanent dipoles.
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    (Original post by sanjukp)
    yeah bt I meant like how do i know that it has hydrogen bonds or does it have permanent dipoles or does it have van der Waals
    like in my example it says CO has a permanent dipole or N2 does not, so how do I know that CO has permanent dipoles.
    N-N same molecule and same attraction of electrons and so no permanent dipole.
    C-O the oxygen has a stronger attraction and so they have a permanent dipole.
    Finding polar molecules and explaining hydrogen bonds are more complex, I would advice you to ask your teacher or use your textbook for those.
 
 
 
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