Advertisements
Advertisements
Question
Answer in brief.
Explain why phenol is more acidic than ethyl alcohol.
Advertisements
Solution
The difference in the acidic character of phenols and alcohol is due to the difference in reactivity of these compounds towards the ionization of the O–H bond. This can be explained as follows:
i. Ionization of alcohols is represented by the following equilibrium
\[\ce{\underset{\text{Alcohol}}{R - OH} + H2O ⇌ \underset{\text{Alkoxide}}{R - O-} + H3O+}\]
The electron-donating inductive effect (+I effect) of the alkyl group destabilizes the alkoxide ion (the conjugate base of alcohol). As a result, alcohol does not ionize much in the water, and behaves like a neutral compound in an aqueous medium.
ii. Ionization of phenol is represented by the following equilibrium
Phenoxide ion, the conjugate base of phenol, is resonance stabilized by delocalization of the negative charge. Therefore, phenol ionizes in an aqueous medium to a moderate extent. Thus phenols are more acidic than ethyl alcohol.
APPEARS IN
RELATED QUESTIONS
Answer in one sentence/ word.
Write the IUPAC name of alcohol having molecular formula C4H10O which is resistant towards oxidation.
Write two points of difference between the properties of phenol and ethyl alcohol.
Answer in brief.
Give the reagents and conditions necessary to prepare phenol from Benzene sulfonic acid.
Answer in brief.
Give the equations of the reactions for the preparation of phenol from isopropyl benezene.
An ether (A), C5H12O, when heated with excess of hot HI produce two alkyl halides which on hydrolysis form compound (B) and (C), oxidation of (B) gave and acid (D), whereas oxidation of (C) gave a ketone (E). Deduce the structural formula of (A), (B), (C), (D), and (E).
Reaction between Grignard reagent and aldehyde other than formaldehyde leads to formation of _______________
Reaction between hot conc. HI and anisole gives ______________
Write IUPAC name of crotonyl alcohol.
With the help of chemical equations show what happens when cumene hydroperoxide is treated with dil. acid.
Write Kolbe’s reaction.
An unknown alcohol is treated with Lucas reagent. Explain how you will determine whether the alcohol is primary, secondary or tertiary. Indicate by chemical equation the reaction between isopropyl alcohol and Lucas reagent.
How will you bring about the following conversions?
2-methyl propan-2-ol to 2-methylpropene
What is the action of conc. H2SO4 on carbolic acid at 373 K.
An organic compound gives hydrogen on reaction with sodium metal. It forms an aldehyde with molecular formula C2H4O on oxidation with pyridinium chlorochromate. Give the chemical equations in support of these observations.
Which of the following compounds is obtained, when phenol react with bromine water?
α-butylene when subjected to hydroboration oxidation reaction, yields ______.
Phenol is obtained from cumene ____________.
Bromination of phenol, will NOT give:
Phenol is ____________.
Phenoxide ion is more stable than phenol due to the ____________.
Which of the following alcohols is least soluble in water?
Which of the following on oxidation yields ethyl methyl ketone?
Identify the role of PDC from the following.
The compound which reacts fastest with Lucas reagent at room temperature is ______.
Which of the following compounds has lowest boiling point?
What is the action of nitrous acid on aniline?
Arrange the following compounds in an increasing order of their solubility in water:
Explain the reaction of 1° and 2° alcohol with oxidising agent chromic anhydride (CrO3).
Write the chemical reaction when hot copper is treated with Vapours of 1° (primary) alcohol.
