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NEETChemistryThermodynamics (C)

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): ( H ₁^ ) for ( H ₂( ~g ) ), and ( Cl ₂( ~g ) ) is zero. Reason (R): ( H _ f ^ ) for every element in its standard state is zero. In the light of the above statements, choose the most appropriate answer from the options given below:

Options

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

Correct answer

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

Step-by-step solution

- Assertion (A): ( H_f^ ) (standard enthalpy of formation) for elements like (H₂(g) ) and ( Cl ₂( ~g ) ) in their standard states is zero, which is true. - Reason (R): The standard enthalpy of formation for any element in its standard state is defined as zero, which correctly explains why ( H_f^ ) for ( H ₂( ~g ) ) and ( Cl ₂( ~g ) ) is zero.

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