The formation of water from hydrogen and oxygen is an example of ________.

The formation of water from hydrogen and oxygen is a combination reaction. In this process, two substances, hydrogen gas (H2) and oxygen gas (O2), combine to form a single product, water (H2O). This reaction is exothermic, releasing energy in the form of heat and light, and follows the equation: 2H2 + O2 → 2H2O.