Give reason for the higher boiling point of ethanol in comparison to methoxymethane

Amines generally have lower boiling points than alcohols of comparable molar mass because amines have weaker hydrogen bonds than alcohols. Consider the compounds methanol and methylamine. Methanol, #"CH"_3"OH"#: molar mass = 32 g/mol; boiling point = 65 °C Methylamine, #"CH"_3"NH"_2#: molar mass = 31 g/mol; boiling point = -6 °C Methanol has strong hydrogen bonds. The strong intermolecular forces give methanol a high boiling point. It is a liquid at room temperature. Methylamine also has hydrogen bonds. But the H-bonds in methylamine are weaker, because N is less electronegative than O. It requires less energy to break the weaker intermolecular forces, so methylamine has a lower boiling point than methanol. Methylamine is a gas at room temperature.

Assertion(A): Boiling point of ethanol is higher in comparison to methoxy methane. Reason (R): Ethanol is associated with inter molecular hydroxide bonding whereas in methoxy methane, inter molecular hydrogen bonding is not present. (a) Both A and R are correct and R is the correct explanation of A. (b) Both A and R are correct but R is not the correct explanation of A. (c) Both A and R are not correct (d) A is correct but R is wrong Categories • • (31.9k) • (8.8k) • (764k) • (248k) • (2.9k) • (5.2k) • (664) • (121k) • (72.1k) • (3.8k) • (19.6k) • (1.4k) • (14.2k) • (12.5k) • (9.3k) • (7.7k) • (3.9k) • (6.7k) • (63.8k) • (26.6k) • (23.7k) • (14.6k) • (25.7k) • (530) • (84) • (765) • (49.1k) • (63.8k) • (1.8k) • (59.3k) • (18.5k) • (1.5k) • (1.9k) • (4.3k) • (188) • (194) • (259) • (211) • (315) • (176) • (183) • (283) • (256) • (369) • (369) • (376) • (349) • (332) • (311) • (1.3k) • (1.4k) • (867) • (1.0k) • (1.5k) • (812) • (1.2k) • (1.7k) • (965) • (18.6k) • (6.1k) • (3.7k) • (4.4k) • (4.2k) • (3.8k) • (24.5k)

Hint: As we know that Hydrogen bond is one of the strongest bonds due to which it is hard to break easily. Methoxymethane does not form H-bonding. Complete step by step answer: Ethanol \[\left( \right)\].

Due to the presence of -OH group, ethanol undergoes intermolecular hydrogen bonding which results in the association of molecules. Therefore, extra energy is required to break those hydrogen bonds. Whereas methoxymethane does not undergo those hydrogen bonding which implies ethanol has a higher boiling point than that of methoxymethane.

Ethanol undergoes intermolecular H-bonding due to the presence of −OH group, resulting in the association of molecules. Extra energy is required to break these hydrogen bonds. On the other hand, methoxymethane does not undergo H-bonding. Hence, the boiling point of ethanol is higher than that of methoxymethane.

(i) Ethanol undergoes intermolecular hydrogen bonding due to the presence of a hydrogen attached to oxygen atom. As a result, ethanol exist as associated molecules and hence it has higher boiling point than methoxy ethane which does not form hydrogen bonds. (ii) Phenol is stronger acid than ethanol because the phenoxide ion left after the release of proton is stabilized by resonance but ethoxide ion is not. Moreover, ethoxide ion is destabilised by +I effect of ethyl group. (iii) Due to –I effect or –R effect of –NO 2 group, the resulting phenolate ion is more stable than phenoxide ion. Therefore o- and p--nitrophenols are more acidic than phenol