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NEETChemistryThermodynamics (C)

Statement I : Combustion of all organic compounds is an exothermic reaction. Statement II : the enthalpies of all elements in their standard states are zero.

Options

  1. ABoth statement I and statement II are incorrect.
  2. BStatement I is correct but statement II is incorrect
  3. CStatement I is incorrect but statement II is correct.
  4. DBoth statements I and statements II are correct.

Correct answer

D. Both statements I and statements II are correct.

Step-by-step solution

- Statement I: Combustion of organic compounds involves breaking chemical bonds and forming new bonds with oxygen, which releases energy. Therefore, combustion of all organic compounds is indeed exothermic. - Statement II: The enthalpy of all elements in their standard state is defined as zero by convention. This is the reference point used to calculate enthalpy changes in reactions.

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