Advertisements
Advertisements
Question
Arrange water, ethanol and phenol in increasing order of acidity and give reason for your answer.
Advertisements
Solution
The increasing order of acidity is ethanol < water < phenol. The phenoxide ion obtained after the removal of a proton is stabilised by resonance whereas the ethoxide ion obtained after the removal of a proton is destabilised by the ‘+I’ effect of the —C2H5 group. Therefore phenol is a stronger acid than ethanol. On the other hand, ethanol is a weaker acid than water because the electron-releasing —C2H5 group in ethanol increases the electron density on oxygen and hence the polarity of the O—H bond in ethanol decreases which results in the decreasing acidic strength. Hence acidic strength increases in the order given above.
APPEARS IN
RELATED QUESTIONS
Write resonance structures of aniline. What is the action of benzene diazonium chloride on ethanol?
Write the mechanism of the following reaction :
\[\ce{C2H5OH->[H2SO4][443K]CH2=CH2 + H2O}\]
Methanol and ethanol are miscible in water due to ____________.
If ethanol dissolves in water, then which of the following would be observed:
Phenol is less acidic than ______.
Phenol can be distinguished from ethanol by the reactions with:
(i) \[\ce{Br2/water}\]
(ii) \[\ce{Na}\]
(iii) Neutral \[\ce{FeCl3}\]
(iv) All the above
Arrange the following compounds in increasing order of acidity and give a suitable explanation.
Phenol, o-nitrophenol, o-cresol
The carbon-oxygen bond in phenol is slightly stronger than that in methanol. Why?
Match the items of column I with items of column II.
| Column I | Column II | |
| (i) | Antifreeze used in car engine | (a) Neutral ferric chloride |
| (ii) | Solvent used in perfumes | (b) Glycerol |
| (iii) | Starting material for picric acid | (c) Methanol |
| (iv) | Wood spirit | (d) Phenol |
| (v) | Reagent used for detection of phenolic group | (e) Ethleneglycol |
| (vi) | By product of soap industry used in cosmetics | (f) Ethanol |
Match the items of column I with items of column II.
| Column I | Column II | |
| (i) | Methanol | (a) Conversion of phenol to o-hydroxysalicylic acid |
| (ii) | Kolbe’s reaction | (b) Ethyl alcohol |
| (iii) | Williamson’s synthesis | (c) Conversion of phenol to salicylaldehyde |
| (iv) | Conversion of 2° alcohol to ketone | (d) Wood spirit |
| (v) | Reimer-Tiemann reaction | (e) Heated copper at 573 K |
| (vi) | Fermentation | (f) Reaction of alkyl halide with sodium alkoxide |
Assertion: Ethanol is a weaker acid than phenol.
Reason: Sodium ethoxide may be prepared by the reaction of ethanol with aqueous \[\ce{NaOH}\].
Alcoholic fermentation is brought about by the action of
Which of the following is known as wood spirit?
If the starting material is 1-methyl-1,2-epoxy cyclopentane, of absolute configuration, decide which one compound correctly represents the product of its reaction with sodium methoxide in methanol.
How methanol is obtained from methanal.
Give IUPAC names of the following compounds:
\[\begin{array}{cc}
\ce{CH3 - CH - CH - CH - CH2-OH }\\
|\phantom{......}|\phantom{......}|\phantom{.......}\\
\ce{Cl}\phantom{....}\ce{CH3}\phantom{...}\ce{CH3}\phantom{.....}
\end{array}\]
3, 3-dimethyl-1-butene was subject to following reactions:
