Final answer:
Oxygen and hydrogen atoms connect underwater through hydrogen bonds caused by the polarity of water molecules, where the oxygen atom becomes slightly negatively charged, and the hydrogen atoms become slightly positively charged, creating an attraction.
Step-by-step explanation:
Oxygen and hydrogen connect underwater due to the polarity of water molecules and the formation of hydrogen bonds. Each water molecule consists of one oxygen atom and two hydrogen atoms. The oxygen atom is more electronegative than the hydrogen atoms, meaning it has a greater tendency to attract electrons. This unequal sharing of electrons causes the oxygen to become slightly negatively charged (δ5-), while the hydrogens acquire a slight positive charge (δ8+).
The partial positive charge of hydrogen attracts the negative charge on the oxygen of a nearby water molecule. This attraction leads to a bond known as a hydrogen bond, which is a strong type of dipole-dipole interaction. Hydrogen bonds are responsible for many of water's special properties including its high boiling point and the fact that ice floats on liquid water. These properties are crucial for sustaining life on Earth.