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Assertion (A): The enthalpy of formation...

Assertion (A): The enthalpy of formation of gaseous oxygen molecules at `298K` and under a pressure of `1 atm` is zero.
Reason (R ) : The entropy of formation of gaseous oxygen molecules under the same condition is zero.

A

If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.

B

If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.

C

If Assertion is True but the Reason is False.

D

If both Assertion & Reason are false.

Text Solution

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The correct Answer is:
C
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ALLEN-THERMODYNAMICS -EXERCISE -4
  1. Assertion (A): There is no reaction known for which DeltaG is positive...

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  2. Assertion :- Absolute value of enthalpy can not be determined. Reaso...

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  3. Assertion :- When a rubber band is stretched entropy increases. Reas...

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  4. Assertion :- At constant pressure for the change H(2)O(s)rarr H(2)O(g)...

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  5. Assertion (A): Enthalpy of graphite is lower than that of diamond. R...

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  6. Assertion (A): The enthalpy of formation of gaseous oxygen molecules a...

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  7. Many endothermic reactions that are not spontaneous at room temperatur...

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  8. Assertion (A): Pressure, volume, and temperature are all extensive pro...

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  9. Assertion (A): For a particular reaction, heat of combustion at consta...

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  10. Assertion :- At constant temp 0^(@)C and 1 atm, the change H(2)O(s)rar...

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  11. Assertion : The increase in internal energy (DeltaE) for the vapouriz...

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  12. Assertion : Water in liqiud state is more stable than ice at room temp...

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  13. Assertion :- In an isolated system the entropy increases due to sponta...

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  14. Assertion :- Entropy is always constant for a closed system. Reason ...

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  15. Assertion :- For an isolated system q is zero. Reason :- In an isola...

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  16. Assertion :- Entropy of system increases for a spontaneous reactions. ...

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  17. Assertion :- Catalyst change Gibbs free energy of system. Reason :- ...

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  18. Assertion :- Q("Surr") is zero for adiabatic process Reason :- Final...

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