What is the volumetric composition of water?

Explanation

**Step-by-Step Solution:**

1. **Identify the Chemical Composition of Water**: Water is a chemical compound made up of two elements: hydrogen (H) and oxygen (O). The chemical formula for water is H2O.

2. **Understand the Ratio of Atoms in Water**: In the formula H2O, the "2" indicates that there are two hydrogen atoms for every one oxygen atom. This means that the ratio of hydrogen to oxygen in water is 2:1.

3. **Relate Atomic Ratio to Volumetric Composition**: The volumetric composition of a substance refers to the proportion of the volume occupied by each component in the mixture. Since the ratio of hydrogen to oxygen in water is 2:1, the volumetric composition of water is also in the same ratio.

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