Boiling Point of Carboxylic Acids

Q. Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass. It is due to their

1. More extensive association of carboxylic acid via van der Waals force of attraction.
2. Formation of carboxylate ion
3. Formation of intramolecular H-bonding
4. Formation of intermolecular H-bonding

Q. $75.2\text{g}$ of $C_6{H}_{5}OH\text{(Phenol)}$ is dissolved in a solvent of $K_f=14$. If the depression in freezing point is $7\text{K}$. Then find the percentage of phenol that dimerizes.
(Given, $\text{molar mass of phenol}=94{\text{g mol}}^{-1}$, mass of solvent $=1\text{kg}$)

Q. Which of the following exhibits the highest boiling point?

1. $0.1\text{m urea}$
2. $0.05\text{m}NaCl$
3. $0.025\text{m}Al(OH{)}_3$
4. $\text{All of the above will have same boiling point}$

Q.

Why amides and carboxylic acids have higher boiling point?

Q.

Consider the following molecules and statements related to them:

(a) (B) is more likely to be crystalline than (A)

(b) (B) has a higher boiling point than (A)

(c) (B) dissolves more readily than (A) in water

Identify the correct option from below:

1. (a) and (c) is true

2. Only (a) is true

3. All are true

4. (a) and (b) are true

Q. $Mg(OH{)}_2$ is partially soluble in water and maximum $pH$ of aqueous solution of $Mg(OH{)}_2$ at ${100}^{o}C$ is 11. The boiling point of aqueous $Mg(OH{)}_2$ solution is [given $K_w$ of water at ${100}^{o}C$ is ${10}^{-13}$ and $(K_b{)}_{H_{2}O}$ is $0.52K{m}^{-1}$ assume $m=M$, boiling point of water is ${100}^{o}C$]

1. ${100.0078}^{o}C$
2. ${101.0026}^{o}C$
3. ${101.26}^{o}C$
4. ${100.26}^{o}C$

Q.

Assertion: Carboxylic acids have higher boiling points than alkanes.

Reason: Carboxylic acids are resonance hybrids.

1. If assertion is false but reason is true.

2. If assertion is true but reason is false.

3. If the assertion and reason both are false.

4. If both assertion and reason are true but reason is not the correct explanation of the assertion.

5. If both assertion and reason are true and the reason is the correct explanation of the assertion.

Q. Q75/200 Correct order of nucleophilicity of the givennucleophiles in ethyl alcohol is phs-, pho- , I- , EtO-

Q. Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass. It is due to their _________.

1. more extensive association of carboxylic acid via van der Waals force of attraction
2. formation of intramolecular H-bonding
3. formation of intermolecular H-bonding
4. formation of carboxylate ion

Q. Identify the correct order of boiling points of the following compounds.
$C{H}_{3}C{H}_{2}C{H}_{2}C{H}_{2}OH,C{H}_{3}C{H}_{2}C{H}_{2}CHO,C{H}_{3}C{H}_{2}C{H}_{2}COOH$
(A) (B) (C)

1. (A) > (B) > (C)
2. (A) > (C) > (B)
3. (C) > (A) > (B)
4. (C) > (B) > (A)

Q. 5. Why carboxylic acids containing even number of carbon atoms have higher melting points?

Q.

Why does sec butyl alcohol have a lesser boiling point than isobutyl alcohol when both are similarly branched?

Q. Assertion
The first nine aliphatic monocarboxylic acids are colourless liquids.
Reason
Carboxylic acids with more than five carbon atoms are insoluble in water.

1. Both Assertion and Reasone are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. why carboxylic acids have more boiling point compared aldehyde, ketones and alcohols but lesser than amides?

Q. The higher boiling points of carboxylic acids are due to

1. Their acidic nature
2. intermolecular hydrogen bonding
3. their dimerisation
4. both (b) and (c)

Q. Why is glycol more viscous than ethanol?

Q. A 1 : 2 mixture (by mole) of ethanol and propanol exerts a vapour pressure of 250 mm Hg. The vapour pressure of propanol in solution is 200 mm Hg, then the vapour pressure of pure ethanol is (in mm Hg)

Q. Carboxylic acids have higher boling points than aldehydes, ketones and even alcohols of comparable molecular mass. It is due to their _________.

1. more extensive association of carboxylic acid via van der waals force of attraction
2. formation of intramolecular H-bonding
3. Formation of strong intermolecular H-bonding than alcohol
4. formation of carboxylate ion

Q. The two compounds pentaamminesulphatocobalt (III) bromide and pentaamminesulphatocobalt (III) chloride respresent :

1. Linkage isomerism
2. Ionization isomerism
3. Coordination isomerism
4. No isomerism

Q. $75.2\text{g}$ of $C_6{H}_{5}OH\text{(Phenol)}$ is dissolved in a solvent of $K_f=14$. If the depression in freezing point is $7\text{K}$. Then find the percentage of phenol that dimerizes.
(Given, $\text{molar mass of phenol}=94{\text{g mol}}^{-1}$, mass of solvent $=1\text{kg}$)

1. $7.5\%$
2. $75\%$
3. $55\%$
4. $5.55\%$

Q. In which of the following solvents does a carboxylic acid dimerize?

1. Carbon tetrachloride
2. Toluene
3. Benzene
4. All of these

Q.

lower alcohols are soluble in water, higher alcohols are not. Why?

Q. Which of the following polymers has ester linkage?

1. Bakelite
2. Terylene
3. Nylon
4. PVC

Q. Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass. It is due to their

1. Formation of intermolecular H-bonding
2. Formation of intramolecular H-bonding
3. More extensive association of carboxylic acid via van der Waals force of attraction
4. Formation of carboxylate ion

Q. has highest boiling point (Given: all has comparable molar mass).

1. Amide
2. Carboxylic acid
3. Acyl chloride
4. Ketone

Q. Which one of the following solvents favors $E2$ reaction?

1. DMSO
2. Ethanol
3. Acetone
4. water

1. 1 & 3
2. 1 & 4
3. 1 & 2
4. 1, 2, 3 and 4

Q. Identify the correct order of boiling points of the following compounds
$C{H}_3\underset{\left(1\right)}{C{H}_2}C{H}_{2}C{H}_{2}OH,\underset{\left(2\right)}{C{H}_{3}C{H}_{2}C{H}_{2}CHO},\underset{\left(3\right)}{C{H}_{3}C{H}_{2}C{H}_{2}COOH}$

1. 1 > 2 > 3
2. 3 > 1 > 2
3. 1 > 3 > 2
4. 3 > 2 > 1

Q.

which will have higher boiling point of 1-bromo butane and 2-bromo-2-methyl propane?

Q.

Assertion: Carboxylic acids have higher boiling points than alkanes.

Reason: Carboxylic acids are resonance hybrids.

1. If both assertion and reason are true and the reason is the correct explanation of the assertion.

2. If both assertion and reason are true but reason is not the correct explanation of the assertion.

3. If assertion is true but reason is false.

4. If the assertion and reason both are false.

5. If assertion is false but reason is true.

Q. Identify the correct order of boiling points of the following compounds.
$C{H}_{3}C{H}_{2}C{H}_{2}C{H}_{2}OH,C{H}_{3}C{H}_{2}C{H}_{2}CHO,C{H}_{3}C{H}_{2}C{H}_{2}COOH$
(A) (B) (C)

1. (A) > (B) > (C)
2. (C) > (A) > (B)
3. (A) > (C) > (B)
4. (C) > (B) > (A)