Final Answer:
Gas is commonly represented as H₂O is, D) Water vapor.
Step-by-step explanation:
Water vapor is commonly represented as H₂O.
H₂O Representation: The chemical formula H₂O is universally recognized as representing water. This formula indicates that a water molecule consists of two hydrogen atoms (H) and one oxygen atom (O).
Water Vapor: While H₂O is the molecular formula for water, the term "water vapor" specifically refers to the gaseous state of water. When water undergoes vaporization, it turns into water vapor, which is an invisible gas.
Understanding the chemical representation of water is fundamental in various scientific disciplines, including chemistry and physics. The formula H₂O is distinct from other options provided:
Therefore, the correct representation of a gas commonly denoted as H₂O is water vapor (option D).