Advanced Placement (AP) Chemistry Practice Exam 2025 - Free AP Chemistry Practice Questions and Study Guide

The correct statement highlights the unique properties of water as a polar solvent, particularly its ability to form hydrogen bonds. Water molecules are polar, possessing a partial negative charge near the oxygen atom and a partial positive charge near the hydrogen atoms. This polarity allows water to interact effectively with other polar substances through dipole-dipole interactions and hydrogen bonding.

When water encounters polar solutes, it can form hydrogen bonds with the solute molecules, facilitating their solubility in water. The ability of water to both accept and donate hydrogen bonds is crucial because it allows for the stabilization of various solute molecules and enhances their solvation, leading to effective dissolution.

The other statements do not accurately reflect the behavior of water with polar substances. Water indeed mixes well with polar substances rather than the assertion that it does not mix at all. While water is less effective at dissolving some polar substances compared to ionic substances, the key distinction of water's hydrogen bonding capabilities points to its effectiveness as a solvent overall. Lastly, water does not form stronger bonds with nonpolar substances; nonpolar solutes do not interact favorably with polar solvents like water, leading to limited solubility.