About solvability

[QuarkQuarkQuark2001]

Is it right that only ionic crystal (ionic compound) can dissolve in water?

And I know carbon dioxide (or ethanol)is molecule and is soluble in water, how does it work?

Would anyone give me some information about it ( better a diagram of dissolving of CO2 into water )

And such as iron(II) ion and sulphate ion, sometimes they mix instead of reacting(not saturated), WHY????

Hope you help !

[budullewraagh]

no

 

think of the organic acids; the O-H bond isn't ionic. CO2 isn't really soluble in H2O...

[QuarkQuarkQuark2001]

no

 

think of the organic acids; the O-H bond isn't ionic. CO2 isn't really soluble in H2O...

]

Thanks. I see.

Covalent compound are not completely dissolve in water.

[budullewraagh]

always remember the rule: like polarity dissolves in like polarity.

a polar solute will dissolve in a polar solvent

a nonpolar solute will dissolve in a nonpolar solvent

a polar solute will not be soluble (well perhaps a little but not much) in a nonpolar solvent

a nonpolar solute will not be soluble (well perhaps a little but not much) in a polar solvent

[ATCC-6538]

It is important that molecule interact with water (with weak bonds, this mean negative enthalpy): glucose (nonionic) forms many H-bonds, ethanol form H-bonds + dipole-dipole interactions, on the other hand, ionic compound AgCl is insoluble, so other thinks are also important (lattice energy etc).......

[apathy]

]

Thanks. I see.

Covalent compound are not completely dissolve in water.

 

ah, i see this a lot. you have confused "dissociate" with "dissolve"

 

ionic compounds will tend to dissociate to some degree or another in water into individual ions. polar covalent compounds will dissolve in water but stay intact as a single neutral molecule.

 

solvation of polar covalent molecules by water involves dipole-dipole interactions between the polar water molecules and polar regions of the covalent molecule.