Why do polar gases dissolve in water easily?

Question

Why do polar gases such as hydrogen chloride dissolve in water easily? Is it because of the dipole effect or some other reason?

thanks :)

Answer 1

Water IS polar. And like-attracts-like. So it makes sense that POLAR molecules would dissolve easily in water.

Answer 2

For starters, water is very polar.  Recall the old adage, "like dissolves like".  Polar solutes are more likely to dissolve in polar solvents.  

Ammonia (polar) and carbon dioxide (nonpolar) will both dissolve in water and react with water to make weakly basic or acidic solutions, respectively.

NH3 + HOH <==> NH4+ + OH-

CO2 + HOH <==> H+ + HCO3-

It is one thing to dissolve in water.  Another to react with water to make new species.  And lastly substances can dissolve in water and then completely dissociate to form ions in solution.

A large amount of HCl will dissolve in water and as it does it will dissociate into ions (unlike NH3 and CO2).  The covalent bond between H and Cl is weak enough so that the pull of the polar water molecules on the polar H-Cl molecule is enough to break the H-Cl bond, with the bonding electrons going to the more electronegative Cl atom forming the chloride ion and the hydrogen ion.

The bottom line is that water is able to dissolve a number of substances (some even nonpolar) and to dissociate some of them because of its polarity and hydrogen bonding.

Answer 3

Yes, it is because of the dipole effect, (+)H----Cl(-),  HCl molecule is surrounded by molecules of water on the side(+) by oxigen and on the side of Cl by hydrogen:

[H2O(-)]....(+)H----Cl(-).....[(+)H2O]

due to that the polar bond between H-Cl is broken and H^+ and Cl^- ions are produced into the solution of gas HCl in water

HCl + H2O ------> H3O^+(aq)   + Cl^-(aq)         aq=H2O

The other reason for other compunds that are soluble in water is making hydrogen bonds betweet the molecules of water and the others compound such as for instance NH3, CH3CH2OH etc