Carboxylic Acid & Derivatives Test - 4

Tertiary alcohols are not oxidised easily but on drastic conditions, these are oxidised to give first ketones and then acids by losing one carbon at each step.

Treatment of sodium salt of phenol with CO_2​ under pressure brings about substitution of the −COOH group for the hydrogen of the ring. This is called as Kolbe's reaction

The esters having active methylene group (- CH₂ -), show Claisen Condensation reaction. As C₆H₅- COOC₂H₅ has no α-hydrogen atom or active methylene group, so it cannot undergo Claisen- Condensation reaction.

Propene reacts with N-bromo succinimide to give allyl bromide, as the allyl hydrogen is comparatively easier to be replaced than vinyl hydrogen.

Among the given acids, perchloric acid HClO₄​ is the strongest acid. This is because the conjugate base ClO₄⁻​ ion is the weakest base.

Among oxyacids of halogens the decreasing order of the acid strength is:

HClO₄​ > HClO₃ ​ >HClO₂ ​ >HClO

Acetic acid (molar mass 60 g/mol) dimerises in benzene due to presence of hydrogen bonding between its molecule hence the molecular weight becomes double than that of normal value.

Hence, in benzene acetic acid show molecular weight of 120 g/mol

pK_a​(CH₃​CO(OOH))=8.2

pK_a​(CH₃​COOH)=4.76

pK_a​(CH₂​Cl⋅COOH)=2.75

pK_a​(CCl₃​COOH)=0.65 and more be the value of pKa​, weaker will be the acid. 

Esters on reaction with excess of Grignard reagent produce 3^o alcohol.