For which parameters the structural isomers C2H5OH and CH3OCH3

• Basic Organic
• Organic Oxygen

For which of the following parameters the structural isomers C₂H₅OH and CH₃OCH₃ would be expected to have the same values? (Assume ideal behavior)

1. Boiling points
2. Vapor pressure at the same temperature
3. Gaseous densities at the same temperature and pressure
4. Heat of vaporization

Answer

Vapor density = Molecular weight/2

As both the compounds have same molecular weights, both will have the same vapour density. Hence, gaseous density of both ethanol and dimethyl ether would be same under identical conditions of temperature and pressure. The rest of these three properties; Vapour pressure, boiling point and heat of vaporization will differ as ethanol has hydrogen bonding whereas ether does not.

The correct option is C.