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NEETChemistryp Block Elements (Group 13 & 14)

Given below are two statements Assertion (A): The enthalpy of formation of graphite is taken as zero. Reason (R): Graphite is thermodynamically most stable allotrope of carbon The correct answer is

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 incorrect
  4. D(A) is incorrect 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

The enthalpy of formation of a substance is the amount of energy required to prepare it from its onstituents in their most stable states. Since graphite is the most stable allotrope of carbon, its enthalpy of formation is zero. Thus, both Assertion (A) and Reason (R) are correct statements and Reason (R) explains Assertion (A).

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