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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 average mass of one (C ) atom is 12.011 amu, which is not the actual mass of one (C ) atom. Reason (R) : Three isotopes ( ¹² C , ¹³ C ) and ( ¹⁴ C ), of (C ) are found in nature. In the light of the above statements, choose the most appropriate answer from the options given below :

Options

  1. AIf (A) & (R) both are correct and (R) is the correct explanation of (A).
  2. BIf (A) & (R) both are correct but (R) is not the correct explanation of (A).
  3. C(A) is correct but (R) is incorrect.
  4. D(A) & (R) both are incorrect.

Correct answer

A. If (A) & (R) both are correct and (R) is the correct explanation of (A).

Step-by-step solution

Assertion (A): "The average mass of one C atom is 12.011 amu, which is not the actual mass of one C atom." - This is correct. The average atomic mass (12.011 amu) is a weighted average of the masses of different carbon isotopes, not the mass of any single carbon atom. Reason (R): "Three isotopes ( ¹² C , ¹³ C ), and ( ¹⁴ C ) of carbon are found in nature." - This is partially correct. While ( ¹² C ) and ( ¹³ C ) are stable and naturally occurring, ( ¹⁴ C ) is radioactive and present in trace amounts. However, the s

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