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Assertion: The enthalpy of formation of ...

Assertion: The enthalpy of formation of gaseous oxygen molecules at `298K` and under1 atm is zero.
Reason: The entropy of formation of gaseous oxygen molecules under the same condition is zero.

A

If both assertion and reason are true and the reason is the correct explanation of the assertion.

B

If both assertion and reason are true but reason is not the correct explanation of the assertion.

C

If assertion is true but reason is false.

D

If the assertion and reason both are false.

Text Solution

Verified by Experts

The correct Answer is:
C
The enthalpy of formation of an element is zero but entropy of the same is not zero.
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Knowledge Check

  • Assertion: The enthalpy of formation of geseous oxygen molecules at 298K and under of 1 atm is zero. Reason: The entropy of formation of gaseous oxygen molecules under the same condition is zero.

    A
    If both the assertion and reason are true and the reason is the correct explanation of the assertion.
    B
    If both the assertion and reason are true but reason is not the correct explantion of the assertion.
    C
    If the assertion is true but reason is false.
    D
    If assertion is false but reason is true.

  • Assertion : The enthalpy of formation of gaseous oxygen molecules at 298 K and under pressure of 1 atm is zero. Reason : The entropy of formation of gaseous oxygen molecules under the same condition is zero.

    A
    If both assertion and reason are true and the reason is the correct explanation of the assertion.
    B
    If both assertion and reason are true but reason is not the correct explanation of the assertion
    C
    If assertion is true but reason is false
    D
    If the assertion and reason both are false.

  • Statement -1 : The enthalpy of formation of gaseous oxygen molecule at 298 K and under a pressure of one atm is zero. Statement -2: The entropy of formation of gaseous oxygen molecules under the same condition is zero.

    A
    Statement -1 is true, Statement -2 is true, Statement -2 is correct explanation for statement -2
    B
    Statement -1 is true, Statement-2 is True, Statement-2 is not a correct explanation for Statement -2
    C
    Statement-1 is true, Statement -2 is False.
    D
    Statement -1 is False, Statement -2 is True.
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