Acidity of Alcohols and Phenols

Q.

In the following compounds,

The order of acidity is

1. III > IV > I > II

2. I > IV > III > II

3. II > I > II > IV

4. IV > III > I > II

Q. Given below are two statements:
Statement I:
The acidic strength of monosubstituted nitrophenol is higher than phenol because of electron withdrawing nitro group.
Statement II:
$o-$nitrophenol, $m-$nitrophenol and $p-$nitrophenol will have same acidic strength as they have one nitro group attached to the phenolic ring.
In the light of the above statements, choose the most appropriate answer from the options given below:

1. Statement I is incorrect but Statement II is correct
2. Both statement I and Statement II are correct
3. Statement I is correct but Statement II is incorrect
4. Both Statement I and Statement II are incorrect

Q. Which one is the most acidic compound?

1. 
2. 
3. 
4. 

Q.

Which of the following is most acidic?
(a) Benzyl alcohol
(b) Cyclohexanol
(c) Phenol
(d) m - chlorophenol

Q.

Give two reactions that show the acidic nature of phenol. Compare acidity of phenol with that of ethanol.

Q. The correct order of reactivity towards electrophillic aromatic substitution reaction for the given compounds is:

1. $C_6{H}_6>C_6{H}_5-OH>C_6{H}_5-Cl>C_6{H}_5-COOH$
2. $C_6{H}_5-OH>C_6{H}_6>C_6{H}_5-Cl>C_6{H}_5-COOH$
3. $C_6{H}_5-Cl>C_6{H}_6>C_6{H}_5-OH>C_6{H}_5-COOH$
4. $C_6{H}_5-OH>C_6{H}_6>C_6{H}_5-COOH>C_6{H}_5-Cl$

Q.

Explain why p-nitrophenol is more acidic than phenol?

Q.

Phenol is less acidic than . . . .
(a) ethanol
(b) o - nitrophenol
(c) o-methylphenol
(d) o - methoxyphenol

Q. Which among the following alcohols is most reactive with sodium wire?

1. Ethanol
2. 2 – propanol
3. 2 – Methyl – 2 – butanol
4. Na metal

Q.

Why is the enthalpy of neutralization of weak acid less than that of a strong acid

Q.

Complete the following reaction:

${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}+{\mathrm{PCl}}_5\to$

Q.

The order of reactivity of following alcohols with halogen acids is .......

(A) $C{H}_{3}C{H}_2-C{H}_2-OH$ (B)

(a) (A) > (B) > (C) (b) (C) > (B) > (A)

(c) (B) > (A) > (C) (d) (A) > (C) > (B)

Q. Which of the following will not react with $NaOH?$

1. 
   
2. $C_2{H}_{5}OH$
3. $C{H}_{3}CON{H}_2$
4. $CH(CN{)}_3$

Q.

Arrange water, ethanol and phenol in increasing order of acidity and give reason for your answer.

Q.

Explain why is ortho nitrophenol more acidic than ortho methoxyphenol?

Q. 100 ml of 0.3 N HCl solution is mixed with 200 ml of 0.6 N H2SO4 solution what is the normality of H2SO4 in the final solution- (1) 0.9 (2) 0.6 (3) 0.7 (4) 0.4

Q. Which of the following will maximum $p{K}_a$ value?

1. o-nitrophenol
2. Phenol
3. o-cresol
4. ethanol

Q. Halogenation of benzene in presence of anhydrous $AlC{l}_3$ is an example of ______ reaction.

1. nucleophilic substitution
2. nucleophilic addition
3. electrophilic substitution
4. free radical substitution

Q.

The ionisation constant of phenol is higher than that of ethanol because

1. Phenoxide ion is bulkier than ethoxide

2. Phenoxide ion is stronger base than ethoxide

3. Phenoxide ion is stabilised through delocalisation

4. Phenoxide ion is less stable than ethoxide

Q.

Assertion (A) Ethanol is a weaker acid than phenol.
Reason (R) Sodium ethoxide may be prepared by the reaction of ethanol with aqueous NaOH.
(a) Assertion and reason both are correct and reason is correct explanation of assertion.
(b) Assertion and reason both are wrong statements.
(c) Assertion is correct statement but reason is wrong statement.
(d) Assertion is wrong statement but reason is correct statement.
(e) Both assertion and reason are correct statements but reason is not correct explanation of assertion.

Q.

Out of o-nitrophenol and o-cresol which is more acidic?

Q. A compound 'X' is acidic and it is soluble in $NaOH$ solution, but insoluble in $NaHC{O}_3$ solution.
Compound 'X' also gives violet colour with neutral $FeC{l}_3$ solution. The compound 'X' is :

Q.

Which of the following compounds will react with sodium hydroxide solution in water?
(a) $C_6{H}_{5}OH$
(b) $C_6{H}_{5}C{H}_{2}OH$
(c) $(C{H}_3{)}_{3}COH$
(d) $C_2{H}_{5}OH$

Q.

Choose the correct word from the bracket and fill in the blanks.

Commercial alcohol is made unfit for drinking by the addition of _________(methanol/ethanol).

Q. Isopropyl alcohol is oxidized with $K_{2}C{r}_2{O}_{7}and{H}_{2}S{O}_4$ to give :

1. $C{H}_{3}COC{H}_3$
2. $C{H}_{3}C{H}_{2}C{H}_{2}COOH$
3. $C{H}_{3}CH=C{H}_2$
4. $C{H}_{3}CHO$

Q.

Which of the following is soluble in water?

1. ${\mathrm{CS}}_2$

2. ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

3. ${\mathrm{CCl}}_4$

4. ${\mathrm{CHCl}}_3$

Q. Nitrobenzene on reacting with $HN{O}_3/H_{2}S{O}_4$ mixture will give

1. 
2. 
3. 
4. Both (b) and (c)

Q.

Write the reactions of (i) aromatic and (ii) aliphatic primary amines with nitrous acid.

Q. Q. For the reaction B₂H₆(g) + 3O₂(g) - - - - - > B2O3 + 3H2O
dU=-2143.2kj
Find dH

Q. The correct increasing order of reactivity for following molecules towards electrophilic aromatic substitution.

1. I < IV < II < III
2. I < IV < III < II
3. I < III < II < IV
4. I < III < IV < II