Phenol is more acidic than alcohol why

- Hint: The acidic character depends on the stability of the ion which is left behind after $-$ is an aromatic ring and it helps in delocalisation of the negative charge inside the ring. This effect is called the resonance effect. It is the withdrawn or releasing effect of electrons from a particular substituent through the delocalisation of a charge. The resonance effect takes place in compounds having a conjugated double bond system. In the conjugated double bond system, there are alternate single and double bonds. The phenoxide ion has an alternate system of single and double bonds. The structure of the phenoxide ion is given below. The chemical formula of ethanol is $$. Note: Always remember that in resonance effect the position of individual atoms does not move at all. Only the electrons in the pi cloud (Double bonded electrons) can be moved. Don’t confuse yourself while drawing resonance structures.

Answer: The acidic nature of alcohol and phenol varies because of the reactivity of these substances towards the ionization reaction involving the O – H bond. Explanation: Ionization of alcohols can be represented as H 2 O + R – OH (alcohol) ⇌ H 3 O + + R – O – (alkoxide) The electron releasing inductive effect shown by the alkyl destabilizes alcohol’s conjugate base (alkoxide ion). So, alcohol never ionizes in water. On the other hand, the phenoxide ion formed after the ionization of phenol in water is a conjugate base and is stabilized through delocalization of the produced negative charge. Thus phenol portrays acidic nature by completing ionization.

Alcohols are very weak Br ønsted acids with pK a values generally in the range of 15 - 20. Because the hydroxyl proton is the most electrophilic site, proton transfer is the most important reaction to consider with nucleophiles. There are small differences in the acidities of aliphatic alcohols in aqueous solution, which are due to differences in structure and, more importantly, solvation. General Assessment of Acidities When considering alcohols as organic reagents, pK as are often used because they reflect reactivity in aqueous solution. In general, alcohols in aqueous solution are slightly less acidic than water. However, the differences among the pK as of the alcohols are not large. This is not surprising because all alcohols are oxy-acids (OH), and the differences in acidities are due to the effect of substituents in the 1-position removed from the acidic site. Moreover, the more highly substituted alcohols vary only in the structure two positions removed from the acidic site. The marginal effects of additional substituents at the carbon tow positions removed from the acidic site are even evident in the gas-phase enthalpies of reaction for the reaction \[ROH \rightarrow RO^- + H^+ \tag\; kJ/mol^2\) Table 1: pK as and gas-phase enthalpies of reaction H water 1633.1 CH 3 methanol 15.5 1597 ± 6 CH 3CH 2 ethanol 15.9 1587 ± 4 (CH 3) 2CH propan-2-ol (isopropyl alcohol) 16.5 1569 ± 4 (CH 3) 3C 2-methylpropan-2-ol (t-butanol) 17 1568 ± 4 C 6H 5 (phenyl) phenol 9.95 1462 ± 10...

Phenol is more acidic than alcohols due to stabilisation of phenoxide ion through resonance. Presence of electron withdrawing group increases the acidity of phenol by , stabilising phenoxide ion while presence of electron releasing group decreases the acidity of phenol by destabilising phenoxide ion

Phenol is having more acidic character than alcohol: • The acidity of any compound is generally defined as the tendency to release or donate hydrogen ions. • In the case of phenol, it loses its hydrogen ion to form the phenoxide ion which gets stabilized by the delocalization of electrons that takes place in phenols by resonance. • Also, in the formed phenoxide ion, the negative charge on the oxygen atom is delocalized around the ring or it gets equally distributed through the compounds. • Also, the presence of the electron-withdrawing group increases the acidity of phenol by stabilizing the resulting phenoxide ion. • However, in the case of ethanol, it is very tough to remove hydrogen ions which makes it less acidic than phenol. Hence, the reason why phenol is having more acidic character than alcohol has been explained above.

Phenol is more acidic than alcohols due to stabilisation of phenoxide ion through resonance. Presence of electron withdrawing group increases the acidity of phenol by , stabilising phenoxide ion while presence of electron releasing group decreases the acidity of phenol by destabilising phenoxide ion.

Which is more acidic p-nitro phenol or phenol? surely para nitro phenol is more acidic than phenol because nitro group is a powerful electron withdrawing group such that it facilitiates the easily removal of protons and it deactivates the benzene ring. in phenol there is no electron withdrawing group so it is less acidic than para nitro phenol

Complete step by step answer: Acidity of any compound generally depends on its tendency to release hydrogen ions. So in case of ethanol it is very tough to remove hydrogen ion from it so we can say that ethanol is less acidic than phenol while on the other side phenol is more acidic than ethanol because it can lose the hydrogen ion very easily because delocalization of electrons takes place in phenols by resonance. When phenol loses its hydrogen ion it gives phenoxide which is stabilized to some extent as negative charge on the oxygen atom is delocalized around the ring means this negative charge is equally distributed through the compounds or we can say that it is shared by a number of carbon atoms in the benzene ring, therefore the more stable the resulted ion is the more likely is to form. One more thing is that the presence of the electron withdrawing group increases the acidity of phenol by stabilizing the resulting phenoxide ion and on the other side presence of the electron releasing group decreases the acidity of phenol by destabilizing the phenoxide ion. Note: Electron withdrawing group draws electron away from the reaction centre while electron releasing group also known as electron donating group releases the electron in the reaction centre.