Polar Molecules: These are molecules that have uneven distribution of charges due to differences in electronegativity between bonded atoms. They can form hydrogen bonds with water, making them hydrophilic.
Hydrophobic Substances: These are substances that do not have an affinity for water. They are typically nonpolar and cannot form hydrogen bonds with water, making them insoluble in water.
Solubility: This is the ability of a substance to dissolve in a solvent such as water. Hydrophilic substances have high solubility in water.