Question

Explain why alcohols are comparatively more soluble in water than the corresponding hydrocarbons.

Answer 1

Hint:In order to solve these types of question we need to know what are the polar solvent and need to explain the polar substance and non-polar solvents why and how are they found after the satisfactory of this we will able to satisfy why the alcohols are more soluble in water than corresponding hydrocarbons.

Complete answer:For solving this first we will need to know what are polar solvents so starting from polar solvents:Polar solvents are found from the large difference in their sizes due to which there is slightly movement of the electron pairs on the side of electronegative atom as a result there will be a partially positive and partially negative charge on that compound. This is due to the large difference in the electronegativity between those two atoms.First we should know that like dissolves like which means the polar solute will dissolve in polar solvent and non-polar solute will dissolve in nonpolar solvent.So we also need to know what type of solvent is water so let me tell you that water is also called “universal solvent” it is because it dissolves more substance than any other liquid. Water molecules have a polar arrangement of the oxygen and hydrogen atoms – one side (hydrogen) has a positive electrical charge and the other side (oxygen) had a negative charge.Due to presence of –OH group, alcohols can form hydrogen bonds with water but hydrocarbons cannot form such hydrogen bonds due to the absence of –OH group.Hence, alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses.Here the intramolecular hydrogen bonding is working because the interaction is between the two different atoms which are solute and solvent. Or we can say that alcohol and water.

Note:Let us have a look what is hydrogen bondingIt is an interaction which involves hydrogen atom located between a pair of another having a high affinity for electrons; such a bond is weaker than ionic bond or covalent bond but are stronger than van der waals forces.Remember one thing that the hydrogen bonding is taking place only when the either of it are present which are fluorine, oxygen and nitrogen along with hydrogen.