Final answer:
The balanced chemical equation for the formation of water from hydrogen and oxygen is 2H₂ + O₂ → 2H₂O, representing a composition reaction where two moles of hydrogen react with one mole of oxygen to produce two moles of water.
Step-by-step explanation:
The balanced equation for the formation of water (H₂O) from hydrogen (H) and oxygen (O₂) is 2H₂ + O₂ → 2H₂O. In this reaction, two moles of hydrogen gas react with one mole of oxygen gas to produce two moles of water. The coefficients in the equation represent molar amounts and ensure that the atoms of each element are equal on both sides of the equation, fulfilling the law of conservation of mass. This is a composition reaction, where only one substance, water, is produced from the reaction of hydrogen and oxygen gases.