The vapor pressure of diethyl ether C2H5OC2H5 is greater than the vapor pressure of ethyl alcohol, C2H5OH at any temperature. Which best accounts for this difference?
Hydrogen bonding of the alcohol.
The difference in vapor pressure between diethyl ether (C2H5OC2H5) and ethyl alcohol (C2H5OH) can be explained by examining their molecular structures and intermolecular forces.
To understand why diethyl ether has a higher vapor pressure than ethyl alcohol, we need to consider the presence of hydrogen bonding. Ethyl alcohol has a hydroxyl group (-OH), which allows for the formation of hydrogen bonds with neighboring alcohol molecules. These hydrogen bonds create stronger intermolecular forces, which require more energy to break and convert the liquid into vapor.
On the other hand, diethyl ether lacks the presence of a hydroxyl group and thus does not form hydrogen bonds to the same extent as ethyl alcohol. Ether molecules exhibit weaker intermolecular forces, primarily consisting of London dispersion forces (also known as van der Waals forces). These forces are weaker and require less energy to break, facilitating the evaporation of diethyl ether into the vapor phase. Therefore, diethyl ether has a higher vapor pressure compared to ethyl alcohol.
In summary, the difference in vapor pressure between diethyl ether and ethyl alcohol is primarily due to the presence of hydrogen bonding in ethyl alcohol, which creates stronger intermolecular forces and increases the energy required for vaporization.