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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): When an ideal gas undergoes adiabatic expansion, its internal energy decreases. Reason (R): According to IUPAC sign convention, the work done by a system during expansion is taken as negative ( w In the light of the above statements, choose the most appropriate answer from the options given below:

Options

  1. ABoth Assertion and Reason are true and Reason is the correct explanation of Assertion.
  2. BBoth Assertion and Reason are true but Reason is NOT the correct explanation of Assertion.
  3. CAssertion is true but Reason is false.
  4. DAssertion is false but Reason is true.

Correct answer

B. Both Assertion and Reason are true but Reason is NOT the correct explanation of Assertion.

Step-by-step solution

Assertion (A) is true: In an adiabatic process, there is no heat exchange ( q = 0 ). During expansion, work is done by the system, so w Reason (R) is true: By IUPAC convention in chemistry, work done by the system (expansion) is taken as negative. However, Reason (R) is NOT the correct explanation for Assertion (A). The decrease in internal energy is due to the combined effect of the process being adiabatic ( q = 0 ) and the system doing work ( w 0 ). Therefore, both statements are true, but the Reason is not the c

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