Question

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

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is incorrect
• D. (A) is incorrect but (R) is correct

Hint:

Graphite is the most stable allotrope of carbon and is used as the reference for enthalpy of formation.

Answer 1

The Correct Option is A

Graphite is the most stable allotrope of carbon and its formation is assigned a zero enthalpy value, as this is used as the reference in thermodynamic calculations. The stability of graphite at standard conditions (298 K and 1 atm) justifies this assignment. Thus, both statements (A) and (R) are correct, and the reason is the correct explanation of the assertion. Therefore, the correct answer is \( \boxed{1} \).