Comment over the following statement
The ratio of atoms can vary in differently prepared samples of a compound.

Answer

To comment on the statement "The ratio of atoms can vary in differently prepared samples of a compound," we need to analyze its validity based on the principles of chemistry.

### Step-by-Step Solution:

1. **Understanding the Statement**: The statement suggests that when a compound is prepared through different methods, the ratio of atoms in that compound may vary.

2. **Defining a Compound**: A compound is a substance formed when two or more elements are chemically bonded together in a fixed ratio. This ratio is defined by the molecular formula of the compound.

3. **Law of Constant Proportions**: According to the law of constant proportions (also known as the law of definite proportions), a chemical compound always contains its component elements in fixed ratio by mass, regardless of how that compound was prepared. This means that the ratio of atoms in a compound remains constant.

4. **Example of Water (H2O)**: For instance, water (H2O) is always composed of 2 hydrogen atoms and 1 oxygen atom, regardless of whether it is obtained from a river, synthesized in a laboratory, or produced through a chemical reaction. The molecular formula H2O indicates that the ratio of hydrogen to oxygen is always 2:1.

5. **Conclusion**: Therefore, the statement "The ratio of atoms can vary in differently prepared samples of a compound" is incorrect. The composition of a compound is independent of the method of preparation, and the ratio of atoms remains constant as dictated by the law of constant proportions.

### Final Comment:
In summary, the statement is incorrect because the ratio of atoms in a compound does not change with different methods of preparation. This is supported by the law of constant proportions, which states that a compound will always have a fixed composition.

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