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Intermolecular forces

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    Another chemistry concept 😅I'm really not grasping about the three forces,vanderwaals ,dipole dipole and hydrogen bonding.i don't understand them at all,can u please explain the differences etc for them?ill be very grateful!thanks xx
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    London Forces or dispersion forces arise because electrons move randomly. In a non-polar molecule like H-H it may move to one end of the bond giving one atom a temporary dipole. This induces a dipole in a neighbouring non-polar molecule if it's oriented the right way. The oppositely charged dipoles (one on original, one on induced) will attract eachother.

    Dipole-Dipole interactions are similar. They involve attraction between oppositely charged dipoles. Except there is no induced dipole. When you have two atoms bonded to eachother with different electronegativity, like C and O, you get a polar bond. Electrons will be more close to the more electronegative atom. The oppositely charged dipoles of neighbouring polar molecules will be attracted to eachother. This is stronger.

    Collectively, these are known as Van Der Waal's forces.

    Hydrogen bonding is a special/stronger type of Dipole-Dipole interaction involving O-H or N-H bonds (O and N being highly electronegative).

    I suggest giving this and this a read.
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    thanks!!!may I ask,how do you identify them?what do you look at xx
    Thank yoi

    (Original post by Kvothe the Arcane)
    London Forces or dispersion forces arise because electrons move randomly. In a non-polar molecule like H-H it may move to one end of the bond giving one atom a temporary dipole. This induces a dipole in a neighbouring non-polar molecule if it's oriented the right way. The oppositely charged dipoles (one on original, one on induced) will attract eachother.

    Dipole-Dipole interactions are similar. They involve attraction between oppositely charged dipoles. Except there is no induced dipole. When you have two atoms bonded to eachother with different electronegativity, like C and O, you get a polar bond. Electrons will be more close to the more electronegative atom. The oppositely charged dipoles of neighbouring polar molecules will be attracted to eachother. This is stronger.

    Collectively, these are known as Van Der Waal's forces.

    Hydrogen bonding is a special/stronger type of Dipole-Dipole interaction involving O-H or N-H bonds (O and N being highly electronegative).

    I suggest giving this and this a read.
 
 
 
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