Question

The following compounds have similar molecular weights. Which has the highest boiling point?

A. CH3OCH3
B. C2H5OH
C. CH3CH2CH3
D. CH3CH=O

Answer 1

The compound C2H5OH, or ethanol, has the highest boiling point due to its ability to form hydrogen bonds, which are stronger than the intermolecular forces present in the other compounds listed.

Step-by-step explanation:

The compound C2H5OH (ethyl alcohol or ethanol) has the highest boiling point among the given compounds. Ethanol is capable of hydrogen bonding because of the presence of an -OH group, which is a significantly stronger intermolecular force than the London dispersion forces and dipole-dipole interactions present in the other compounds. This makes ethanol's boiling point higher compared to CH3OCH3 (dimethyl ether), CH3CH2CH3 (propane), and CH3CH=O (acetaldehyde). While all three compounds are similar in molecular weight, the type of intermolecular forces they experience is different. The ordering of boiling points from lowest to highest is as follows: CH3CH2CH3 < CH3OCH3 < CH3CH=O < C2H5OH.

Answer 2

`\Huge \boxed{\mathrm{C_2H_5OH}}`

Step-by-step explanation:

CH₃OCH₃ (Dimethyl ether) has a boiling point of -23 °C

C₂H₅OH (Ethanol) has a boiling point of 78.37 °C

CH₃CH₂CH₃ (Propane) has a boiling point of -42 °C

CH₃CHO (Acetaldehyde) has a boiling point of 20.2 °C

C₂H₅OH (Ethanol) has the highest boiling point.