Which best describes how charges are distributed on a water (H_2O) molecule?

• A. The oxygen atom has a partial negative charge, while the hydrogen atoms have partial positive charges.
• B. The hydrogen atoms have partial negative charges, and the oxygen atom has a partial positive charge.
• C. There is no charge separation; the molecule is nonpolar.
• D. All atoms in the molecule have equal charge distribution.

Answer: (A)

Verified step by step guidance

1. Recognize that water (H\_2O) is a polar molecule due to the difference in electronegativity between oxygen and hydrogen atoms.
2. Understand that oxygen is more electronegative than hydrogen, meaning oxygen attracts the shared electrons in the covalent bonds more strongly.
3. This unequal sharing of electrons causes the oxygen atom to acquire a partial negative charge (\( \delta^- \)) because it has a higher electron density around it.
4. Conversely, the hydrogen atoms have a lower electron density and thus acquire partial positive charges (\( \delta^+ \)).
5. Conclude that the molecule has a dipole moment with a partial negative charge on oxygen and partial positive charges on the hydrogens, making the molecule polar.