Which of the following statements is/are CORRECT? Statement I: Atoms of different elements combine in definite proportions to form compounds. Statement II: In a pure chemical compound, elements are always present in a definite proportion by mass.
Both statements I and II are correct
Statement I paraphrases the law of definite proportions extended to combining ratios: atoms of different elements combine with each other in simple, fixed whole-number ratios to form compounds. Water is always H2O, ammonia is always NH3. This is a foundational idea of Dalton's atomic theory and is correct.
Statement II is the law of constant (definite) proportions itself: in any pure sample of a given compound, the constituent elements are always present in the same fixed ratio by mass, regardless of source or method of preparation. Pure water everywhere contains hydrogen and oxygen in a 1:8 mass ratio. Statement II is also correct.
Both statements describe accepted chemical laws, so both are correct.
Hence, the answer is Both statements I and II are correct.
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