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Calcium carbonate is naturally available as limestone and can also be synthesized from quick lime. It is seen that the compositions of the elements in both the natural and synthetic calcium carbonate are same. The validity of which one among the following laws is confirmed by this observation?
Explanation
The observation that natural limestone and synthetic calcium carbonate have the same elemental composition confirms the Law of Definite Proportion (also known as the Law of Constant Composition). Formulated by Joseph Proust, this law states that a chemical compound always contains its constituent elements in the same proportion by mass, regardless of its source or method of preparation. Whether calcium carbonate is obtained from natural sedimentary deposits like limestone or synthesized from quicklime, the ratio of calcium, carbon, and oxygen remains constant. This distinguishes it from the Law of Multiple Proportions, which deals with different compounds formed from the same elements, and the Law of Conservation of Mass, which concerns mass parity in reactions. Avogadro's law relates to gas volumes and molecules, which is not applicable to the solid composition of calcium carbonate.
Sources
- [1] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 7: Resources > Natural Resources of India > p. 24
- [2] https://www.jstor.org/stable/228679