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Why are haloalkanes insoluble in water and soluble in organic solvents?

I don't really understand this. Could someone enlighten me please?
Thank you very much
Original post by lorobolorolo
I don't really understand this. Could someone enlighten me please?
Thank you very much


Because they cannot form H-bonds with water, so the water prefers to bond to itself.

In non-polar solvents the attraction between the haloalkanes and the solvent is a strong (or stronger) than the attraction of solvent for solvent particles.
Original post by charco
Because they cannot form H-bonds with water, so the water prefers to bond to itself.

In non-polar solvents the attraction between the haloalkanes and the solvent is a strong (or stronger) than the attraction of solvent for solvent particles.



What is a haloalkane? What is a H-bond?
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AtomicMan
13
Original post by Drederick Tatum
What is a haloalkane? What is a H-bond?


Haloalkanes are alkanes that have a halogen (flourine, chlorine, bromine, iodine or astatine) in it in place of a hydrogen atom.

H-bond is a hydrogen bond
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Avatar for lorobolorolo
lorobolorolo
OP
7
Original post by charco
Because they cannot form H-bonds with water, so the water prefers to bond to itself.

In non-polar solvents the attraction between the haloalkanes and the solvent is a strong (or stronger) than the attraction of solvent for solvent particles.


Thanks i understand it now. I would like to give u a thumbs up but apparently I already gave u one so tsr is not letting me.

Could u also explain to me how ionic compounds are soluble in water?? They can't form hydrogen bonds with the water molecules..so how does that work?
Original post by lorobolorolo
Thanks i understand it now. I would like to give u a thumbs up but apparently I already gave u one so tsr is not letting me.

Could u also explain to me how ionic compounds are soluble in water?? They can't form hydrogen bonds with the water molecules..so how does that work?


Wate molecules are polar, they surround the ions using electrostatic forces of attraction. These are effectively bonds and their formation is exothermic. The formation is called hydration and the energy change is called the hydration enthalpy.

Cu(H2O)6.gif

The solubility of and ionic compound is a balance between the energy needed to break the lattice and the exothermic hydration enthalpy of the ions, with the entropy change thrown in...
(edited 11 years ago)
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Avatar for lorobolorolo
lorobolorolo
OP
7
Original post by charco
Because they cannot form H-bonds with water, so the water prefers to bond to itself.

In non-polar solvents the attraction between the haloalkanes and the solvent is a strong (or stronger) than the attraction of solvent for solvent particles.


Sorry about all these questions but I was just thinking about haloalkanes. Why can't they form hydrogen bonds with water? Don't halgoens have a lone pair and they are highly electronegative. So shouldn't they be able to form hydrogen bonds??
In order to form hydrogen bonds a molecule should have a hydrogen tht is DIRECTLY attched to an elctronegative element such as oxygen,fluorine or nitrogen.In haloalkanes we dont have a hydrogen attched to an elctronegatve element , even if u consider some haloalkane with flurorne in it u would say it should form h- bonds but no it doest as F is not atthched to hydrogen rather a Carbon which in turn is attched to hydrogen but as i told in order for h-bonds to form Flourine should be DIRECTLY bonded to a hydrogen.
Original post by lorobolorolo
Sorry about all these questions but I was just thinking about haloalkanes. Why can't they form hydrogen bonds with water? Don't halgoens have a lone pair and they are highly electronegative. So shouldn't they be able to form hydrogen bonds??


Those are not the requirements for hydrogen bonding to occur
Fluorine can form hydrogen bonds with water..
yes fluorine can but not in a haloalkane
Debatable, you'd get H bonding in CF3H, for sure. You get hydrogen bonding in chloroform.

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