Dimethyl ether intermolecular forces

In dimethyl ether, the oxygen atom is sp3 hybridized. In creating two single bonds, each bond is formed by the overlap of one of its sp3 hybrid orbitals with the sp3 hybrid orbital on the adjacent carbon atom. Each of the remaining two hybrid orbitals on the oxygen atom contain a lone pair of electrons. The resulting molecule is polar. The intermolecular forces found operating between molecules of dimethyl ether are therefore dipole-dipole interactions and London forces. 

Example Based on intermolecular forces, predict which will have the higher vapor pressure and higher boiling point, water or dimethyl ether, CH3-O-CH3. 

Explanation Water is a polar substance with strong intermolecular hydrogen bonds. Dimethyl ether is a polar material with weaker intermolecular forces (dipole-dipole). It will... 

Briefly describe the bonding around the oxygen atom in dimethyl ether. What intermolecular forces are found in this ether ... 

Two molecules that contain the same number of each kind of afom but that have different molecular structures are said to be isomers of each other. For example, both ethyl alcohol and dimethyl ether (shown below) have the formula C2HgO and are isomers. Based on considerafions of intermolecular forces, which substance would you expect to be more volatile Which would you expect to have the higher boiling point Explain. 

Ethanol molecules can attract each other with strong hydrogen bonds dimethyl ether molecules cannot (why ). The surface tension of ethanol is greater than that of dimethyl ether because of stronger intermolecular forces (the hydrogen bonds). Note that ethanol and dimethyl ether have identical molar masses and molecular formulas so attractions resulting from dispersion forces will be equal. 

Molecules of dimethyl ether, because they lack a hydrogen atom attached to a strongly electronegative atom, cannot form strong hydrogen bonds to each other. In dimethyl ether the intermolecular forces are weaker dipole—dipole interactions. 

Draw dimethyl ether and ethanol and analyze their intermolecular forces to explain the observed trend. 

Consider the physical properties of the two isomeric compounds, ethanol and dimethyl etiher, presented in Table 7.3. Since the dipole moment values are so close, how can we explain the much higher normal boiling point temperature of ethanol Or, the more than double amount of energy needed to vaporize one mole of ethanol as compared to one of dimethyl ether In other words, what kind of intermolecular forces are responsible for these differences ... 

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