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NEETChemistrySome Basic Concepts of Chemistry

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The empirical formula of a hydrocarbon containing 75 % carbon and 25 % hydrogen by mass is CH ₄ . Reason (R): The empirical formula is determined by finding the simplest whole-number ratio of the moles of constituent elements, which is obtained by dividing their mass percentages by their respective

Options

  1. ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
  2. BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
  3. C(A) is correct but (R) is not correct
  4. D(A) is not correct but (R) is correct

Correct answer

A. Both (A) and (R) are correct and (R) is the correct explanation of (A)

Step-by-step solution

Evaluating the Assertion (A): Mass percentage of C = 75 % , H = 25 % . Moles of C = 75 12 = 6.25 Moles of H = 25 1 = 25 Simplest ratio of C : H = 6.25 6.25 : 25 6.25 = 1 : 4 . Thus, the empirical formula is CH ₄ . The Assertion is correct. Evaluating the Reason (R): The empirical formula represents the simplest whole-number ratio of various atoms present in a compound. This ratio is indeed calculated by dividing the mass percentage of each element by its atomic mass to get relative moles, and then finding their sim

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