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Hydrocarbons — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryHydrocarbons1 Mark
MCQ
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 $(A)$ : Nitration of benzene with nitric acid requires the use of concentrated sulphuric acid.
Reason $(R)$ : The mixture of concentrated sulphuric acid and concentrated nitric acid produces the electrophile, $\text{NO}_2^+$.
  • ✓
    Both $A$ and $R$ are correct and $R$ is the correct explanation of $A.$
  • B
    Both $A$ and $R$ are correct but $R$ is not the correct explanation of $A.$
  • C
    Both $A$ and $R$ are not correct.
  • D
    $A$ is not correct but $R$ is correct.
✓

Answer

Correct option: A.
Both $A$ and $R$ are correct and $R$ is the correct explanation of $A.$
In nitration, benzene is treating with nitrating mixture, i.e. conc. $\mathrm{HNO}_3$ and $\mathrm{H}_2 \mathrm{SO}_4$ and $\mathrm{H}_2 \mathrm{SO}^4$ helps in furishing $\mathrm{N}_2^{+} ($Electrophile$).$​​​​​​​

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