Question

Question: Hydrogen chloride (HCl) gas is much more soluble than propane gasin water, even though HCl has a lower boiling point. Explain.

Short answer

Answer

HCl is much more soluble in water than propane gas because both HCl and water are polar in nature while propane in non-polar in nature.

Step-by-step solution

Solubility  

Solubility of any substance depends on the following rule: like dissolves like, it means polar solvent dissolves polar substances and vice versa.

Check polarity of both solvent and solute 

Our solvent is water which is polar in nature. HCl is a polar molecule and propane is a non-polar molecule. So, according to the rule HCl is soluble in water.

Reason for high solubility of HCl in water

The solubility increases with the strength of the intermolecular interactions between the molecules of the solute and the solvent. HCl molecule breaks down into ions when dissolved in water and forms strong intermolecular interactions with water. This is the reason behind greater solubility of HCl in water.