For which compound is pK_a the highest? | vedclass

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(B) The $pK_a$ value is inversely proportional to the acidity of a compound. $A$ higher $pK_a$ value indicates lower acidity.Acidity is determined by

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$CH_3CH_2COOH$

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(B) The $pK_a$ value is inversely proportional to the acidity of a compound. $A$ higher $pK_a$ value indicates lower acidity.Acidity is determined by the stability of the conjugate base, which is influenced by the inductive effects of the substituents attached to the $-COOH$ group.Electron-withdrawing groups ($-I$ effect) increase acidity, while electron-donating groups ($+I$ effect) decrease acidity.Comparing the given compounds:$1$. $HCOOH$ (Formic acid): No alkyl group attached.$2$. $CH_3CH_2COOH$ (Propanoic acid): Contains an ethyl group, which is electron-donating ($+I$ effect).$3$. $C_6H_5CH_2COOH$ (Phenylacetic acid): Contains a phenyl group, which is electron-withdrawing ($-I$ effect).$4$. $ClCH_2CH_2COOH$ ($3$-Chloropropanoic acid): Contains a chlorine atom, which is strongly electron-withdrawing ($-I$ effect).Since the ethyl group in $CH_3CH_2COOH$ is electron-donating, it destabilizes the carboxylate anion, making it the least acidic among the options. Therefore, $CH_3CH_2COOH$ has the highest $pK_a$ value.

Column-$1$ (Acid)	Column-$2$ ($pK_a$ value)
$A. CH_3COOH$	$I. 0.23$
$B. F_3CCOOH$	$II. 3.41$
$C. \text{Benzoic acid}$	$III. 4.19$
$D. p\text{-Nitrobenzoic acid}$	$IV. 4.76$

For which compound is $pK_a$ the highest?

Similar Questions

Which class of compounds shows hydrogen bonding even more than in alcohols?

Match the following:
Column-$1$ (Acid) Column-$2$ ($pK_a$ value)
$A. CH_3COOH$ $I. 0.23$
$B. F_3CCOOH$ $II. 3.41$
$C. \text{Benzoic acid}$ $III. 4.19$
$D. p\text{-Nitrobenzoic acid}$ $IV. 4.76$

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Which of the following statements is true for formic acid $(HCOOH)$?

Identify compound $A$ used in the following reaction: Benzoic acid $\xrightarrow[\Delta]{A}$ Benzoyl chloride + Phosphorous oxychloride + Hydrogen chloride

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