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MODEL PAPER 4 — Chemistry STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 41 Mark
Question
Assertion $(A):$ Aqueous solution of phenol is called as carbonic acid.
Reason $(R):$ Increasing order of acidity of phenols is m nitrophenol $ >o-$nitrophenol $ >p-$nitrophenol.
✓

Answer

Aqueous solution of phenol is called carbolic acid. Electron withdrawing groups such as $-NO_2, -CN, -X-$ increase the acidity.
The increase is more at $o$ and $p -$ positions than at m-position.
i.e. $p-$nitrophenol $ >o-$nitrophenol $ >m-$nitrophenol.

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