Which of the following is considered a polar solvent?

Water is considered a polar solvent due to its molecular structure and properties. In water molecules, the oxygen atom is more electronegative than the hydrogen atoms, which creates a dipole moment. This dipole results in a positive charge on one end of the molecule (the hydrogen atoms) and a negative charge on the other (the oxygen), allowing water to interact favorably with other polar substances and ionic compounds. This characteristic makes it an excellent solvent for many substances, particularly those that are also polar or ionic, as they can dissolve in water through interactions like hydrogen bonding.

In contrast, the other substances listed—hexane, benzene, and octane—are nonpolar solvents. They do not have a significant charge separation within their molecular structure, which limits their ability to dissolve polar substances. This distinction is critical in understanding solvent-solute interactions in various chemical processes.