For which of the following parameters the structural isomers `C_(2)H_(5)OH` and `CH_(3)OCH_(3)` would be expected to have the same values (Assume ideal behaviour)

Options

A. Boiling points
B. Vapour pressure at the same temperature
C. Heat of vaporization
D. Gaseous densities at the same temperature and pressure

Explanation

To determine which parameters the structural isomers C2H5OH (ethanol) and CH3OCH3 (dimethyl ether) would be expected to have the same values, we need to analyze the properties of these compounds.

### Step 1: Identify the Structural Isomers
- C2H5OH is ethanol, which contains an -OH (hydroxyl) group.
- CH3OCH3 is dimethyl ether, which contains an ether functional group.

### Step 2: Analyze the Properties
We will consider various physical properties such as:
1. Molar mass
2. Density
3. Boiling point
4. Vapor pressure
5. Refractive index

### Step 3: Compare Molar Mass
- Molar mass of C2H5OH (ethanol) = 2(12) + 6(1) + 16 = 46 g/mol
- Molar mass of CH3OCH3 (dimethyl ether) = 2(12) + 6(1) + 16 = 46 g/mol
- **Conclusion**: Both have the same molar mass.

### Step 4: Compare Density
- At room temperature, the density of ethanol is approximately 0.789 g/cm³.
- The density of dimethyl ether is approximately 0.714 g/cm³.
- **Conclusion**: Densities are different.

### Step 5: Compare Boiling Point
- Boiling point of ethanol is about 78.37 °C.
- Boiling point of dimethyl ether is about -24.9 °C.
- **Conclusion**: Boiling points are different.

### Step 6: Compare Vapor Pressure
- Vapor pressure varies with temperature, but at a given temperature, ethanol and dimethyl ether will have different vapor pressures due to their different intermolecular forces.
- **Conclusion**: Vapor pressures are different.

### Step 7: Compare Refractive Index
- The refractive index of ethanol is about 1.36.
- The refractive index of dimethyl ether is about 1.31.
- **Conclusion**: Refractive indices are different.

### Final Conclusion
The only parameter for which the structural isomers C2H5OH and CH3OCH3 would be expected to have the same value is **molar mass**.