Ethylene glycol is the more viscous liquid compared to ethanol due to its greater ability to form hydrogen bonds, resulting from the presence of two hydroxyl groups. Option a. Ethylene glycol, because this molecule has a greater ability for hydrogen bonding is the correct answer.
The more viscous liquid between ethylene glycol and ethanol is ethylene glycol. This is due to its greater ability for hydrogen bonding.
Ethylene glycol has two hydroxyl (-OH) groups, which can form hydrogen bonds with neighboring molecules. Hydrogen bonding is a strong intermolecular force that leads to increased viscosity. The presence of multiple hydrogen bonding sites in ethylene glycol allows for more extensive and stronger intermolecular interactions, resulting in higher viscosity.
On the other hand, ethanol has only one hydroxyl group, limiting its ability to form hydrogen bonds compared to ethylene glycol. While ethanol also experiences hydrogen bonding, the presence of a single hydrogen bonding site results in weaker intermolecular interactions and lower viscosity.
Dispersion forces, which arise from temporary fluctuations in electron distribution, are another intermolecular force that affects viscosity. However, in this case, the difference in dispersion forces between ethylene glycol and ethanol is not significant enough to be the primary factor determining the difference in viscosity.
The greater ability of ethylene glycol to form hydrogen bonds, due to its two hydroxyl groups, leads to stronger intermolecular interactions and higher viscosity compared to ethanol.