H2O is water because it's the chemical formula describing a molecule composed of two hydrogen atoms (H) and one oxygen atom (O) bonded together.
To understand why this specific combination creates water, let's break it down:
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Elements: Water is a compound, meaning it's made of two or more different elements chemically bonded. The elements involved are hydrogen and oxygen.
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Atoms: An atom is the smallest unit of an element. Water consists of two hydrogen atoms and one oxygen atom.
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Molecular Structure: These atoms are not just mixed; they are chemically bonded in a specific arrangement. The oxygen atom shares electrons with each of the hydrogen atoms, forming covalent bonds. This specific molecular structure gives water its unique properties.
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Chemical Formula: The chemical formula H2O represents this specific arrangement: two hydrogen atoms (H2) bonded to one oxygen atom (O).
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Properties of Water: This unique molecular structure leads to water's remarkable properties, like its ability to dissolve many substances (being a universal solvent), its high surface tension, and its unusual density behavior (ice is less dense than liquid water). These properties are essential for life as we know it.
In simple terms, the combination of two hydrogen atoms and one oxygen atom, bonded together in a specific molecular arrangement, defines a water molecule. Therefore, H2O is water.
