The correct order of acidity for the following compounds is:
The correct order of acidity for the following compounds is:
$II < I V < I < III$
$II < III < I < IV$
$II < III < IV < I$
$III < II < I < IV$
Solution
Compound IV is a carboxylic acid whereas others are alcohols. So IV is most acidic, amongst the alcohols. Presence of $-\mathrm{NO}_{2}$ increases acidic strength while the presence of $-\mathrm{CH}_{3}$ lowers. Amongst I and III, more acidic is $\mathrm{I}$ as $-\mathrm{NO}_{2}$ exerts it's $-\mathrm{R}$ influence in para position.
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