During the preparation of esters from carboxylic acid andalcohol In thepresence of acid catalyst, the water or the ester should be removed as soon as it is formed. Give reason.

Give possible explanation fòr each of the following: i. Cyclohexanone forms cyanohydrin in good yield but 2,2,6 -trimethylcyclohexanone does not. ii. There are two -NH_2 groups in semicarbazide. However, only one is involved in the formation of semicarbazones. iii. During the preparation of esters from a carboxylic acid and an alcohol in the presence of an acid catalyst, the water or the ester should be removed as soon as it is formed.

In the reaction of carboxylic acid with CH_(2)N_(2) to form an ester, the reaction intermediate is

Preparation of ethers by acid dehydration of secondary or tertiary alcohols is not a suitable method. Give reason.

Carboxylic acids, esters and amides do not give the properties of ketones. It is due to

Assertion: Commercially carboxylic acids are reduced to alcohols by converting them to the esters followed by their reduction using catalytic hydrogenation. Reason: LiAlH_4 can also reduce.carboxylic acids to primary, alcohols but LiAlH_4 is an expensive reagent and used for preparing special chemicals only

Reaction of cyclohexanone with dimethylamine in the presence of catalytic amount of an acid forms a compound if water during the reaction is continuously removed. The compound formed is generally known as

Paragraph Carboxylic acids are distinctly acidic because they ionize in water to give hydronium ions: RCOOH+H_(2)O hArr RCOO^(-) +H_(3)O^(+) The acidic strength depends upon the extent of ionizations of the acid and the stability of the anion formed. The acidic strength can also be expressed in terms of dissociation constant K_(a) or pK_(a) which are related as pK_(a)= -log K_(a) . Most unsubstituted carboxylic acids have K_(a) values in the range of 10^(-4) to 10^(-5) (pK_(a) =4-5) . The substitutents have marked effect on the acidic strength of carboxylic acids. Any group that stabilizes the carboxylate ion more than the carboxylic acid group will increase the acidic strength, and the group which destabilizes the carboxylate group more than the carboxylic acid group will decrease the acidic strength. In a similar manner, the electron-releasing groups makes benzoic acid weaker, while the electron-withdrawing groups make benzoic acid stronger. The ortho isomer of every substituted benzoic acid (whether electron releasing or electron withdrawing) is the strongest among the three isomers due to ortho effect. Which of the following is the weakest acid?

Paragraph Carboxylic acids are distinctly acidic because they ionize in water to give hydronium ions: RCOOH+H_(2)O hArr RCOO^(-) +H_(3)O^(+) The acidic strength depends upon the extent of ionizations of the acid and the stability of the anion formed. The acidic strength can also be expressed in terms of dissociation constant K_(a) or pK_(a) which are related as pK_(a)= -log K_(a) . Most unsubstituted carboxylic acids have K_(a) values in the range of 10^(-4) to 10^(-5) (pK_(a) =4-5) . The substitutents have marked effect on the acidic strength of carboxylic acids. Any group that stabilizes the carboxylate ion more than the carboxylic acid group will increase the acidic strength, and the group which destabilizes the carboxylate group more than the carboxylic acid group will decrease the acidic strength. In a similar manner, the electron-releasing groups makes benzoic acid weaker, while the electron-withdrawing groups make benzoic acid stronger. The ortho isomer of every substituted benzoic acid (whether electron releasing or electron withdrawing) is the strongest among the three isomers due to ortho effect. Which of the following statement is not correct?