Ether at room temperature is placed in a flask connected by a rubber tube to a vacuum pump. The pump is turned on, and the ether begins boiling. Explain why this occurs.

Verified step by step guidance

Step 1: Understand that boiling occurs when the vapor pressure of a liquid equals the external pressure acting on it.

Step 2: Recognize that at room temperature, the vapor pressure of ether is lower than atmospheric pressure, so it does not boil under normal conditions.

Step 3: Note that when the vacuum pump is turned on, it reduces the external pressure inside the flask.

Step 4: Realize that as the external pressure decreases, it eventually becomes equal to the vapor pressure of ether at room temperature.

Step 5: Conclude that when the vapor pressure equals the reduced external pressure, the ether begins to boil.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Boiling Point and Vapor Pressure

The boiling point of a liquid is the temperature at which its vapor pressure equals the external pressure. Ether has a relatively low boiling point, and as the pressure decreases, its vapor pressure can exceed the external pressure at room temperature, leading to boiling.

Effect of Pressure on Phase Changes

The phase of a substance can change based on the pressure applied. Lowering the pressure using a vacuum pump reduces the external pressure on the ether, allowing it to transition from liquid to gas at a lower temperature than its normal boiling point.

Vacuum Pump Functionality

A vacuum pump removes air and other gases from a sealed environment, creating a low-pressure system. This reduction in pressure facilitates the boiling of liquids like ether at room temperature, as the liquid molecules can escape into the gas phase more easily.

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