To determine which liquid has the highest vapor pressure at room temperature, we need to understand the relationship between boiling point and vapor pressure. A liquid with a lower boiling point has a higher vapor pressure at a given temperature, because it requires less heat to reach the point of boiling where it transitions from liquid to gas.
Here’s the detailed step-by-step process to determine which liquid has the highest vapor pressure:
1. List the boiling points of the liquids:
- Water: 100°C
- Ethanol: 78.5°C
- Methanol: 64.96°C
- Diethyl ether: 4.5°C
2. Determine the relationship between boiling point and vapor pressure:
- The liquid with the lowest boiling point will have the highest vapor pressure at room temperature.
3. Compare the boiling points:
- Water: 100°C
- Ethanol: 78.5°C
- Methanol: 64.96°C
- Diethyl ether: 4.5°C
4. Identify the liquid with the lowest boiling point:
- Among the given liquids, Diethyl ether has the lowest boiling point of 4.5°C.
5. Conclusion:
- Since Diethyl ether has the lowest boiling point, it has the highest vapor pressure at room temperature.
Therefore, the liquid with the highest vapor pressure at room temperature is Diethyl ether with a boiling point of 4.5°C.
