Kaplan Nursing Entrance Practice Exam

What type of bond is present in H2O?

1. Ionic bond

2. Nonpolar covalent bond

3. Polar covalent bond

4. Hydrogen bond

The correct answer is: Polar covalent bond

In H2O, the type of bond that is present is a polar covalent bond. Water molecules consist of two hydrogen atoms and one oxygen atom. The oxygen atom is more electronegative than the hydrogen atoms, meaning that it has a stronger attraction for the electrons that are shared with hydrogen. This results in a partial negative charge on the oxygen atom and a partial positive charge on the hydrogen atoms, creating a dipole within the molecule. This polarity is significant because it allows water to engage in hydrogen bonding with other water molecules and with other polar substances, which is crucial for many of its unique properties, such as its high surface tension and solvent capabilities. The polar covalent bond is fundamental in giving water its characteristics that support life, including temperature regulation and as a universal solvent. In contrast, ionic bonds occur between oppositely charged ions, nonpolar covalent bonds involve equal sharing of electrons between atoms with similar electronegativities, and hydrogen bonds are interactions that can occur as a result of the polar nature of the molecule, but they are not the bonds that are formed within the molecule itself.