MCQ
Note : In the following questions a statement of Assertion $(A)$ followed by a statement of Reason $(R)$ is given. Choose the correct option out of the choices given below each question.
Assertion $(A)$ : Among the two $O–H$ bonds in $\mathrm{H}_2\mathrm{O}$ molecule, the energy required to break the first $O – H$ bond and other $O – H $ bond is the same.
Reason $(R)$ : This is because the electronic environment around oxygen is the same even after breakage of one $O – H$ bond.
  • A
    Both $A$ and $R$ are true but $R$ is not the correct explanation of $A.$
  • B
    $A$ is true but $R$ is false.
  • C
    $A$ is false but $R$ is true.
  • Both $A$ and $R$ are false.

Answer

Correct option: D.
Both $A$ and $R$ are false.
The bond enthalphy in $H-O$ is not same for both the $O-H$ bonds. because electronic charge atom is different one $O-H$ bond.

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