1. What is Effusion Rate?

The effusion rate describes how quickly a gas escapes through a tiny hole into a vacuum. According to Graham's law, the rate is inversely proportional to the square root of the molecular weight of the gas.

2. How Does the Calculator Work?

The calculator uses the effusion rate equation:

Where:

• \( \text{Rate} \) — Relative effusion rate (unitless)
• \( \text{MW} \) — Molecular weight of the gas (g/mol)

Explanation: Lighter gases effuse faster than heavier ones. The rate is relative to some reference gas (typically hydrogen).

3. Importance of Effusion Rate Calculation

Details: Effusion rates are important in gas separation processes, vacuum systems, and understanding gas behavior in confined spaces.

4. Using the Calculator

Tips: Enter the molecular weight of the gas in g/mol. The result is a relative rate compared to other gases.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between effusion and diffusion?
A: Effusion is gas escaping through a tiny hole, while diffusion is gas spreading out in a space.

Q2: How does temperature affect effusion rate?
A: Temperature affects absolute rates, but the relative rates between gases remain proportional to 1/√MW.

Q3: What are typical applications of effusion?
A: Uranium enrichment, leak detection, and creating molecular beams in physics experiments.

Q4: Why is the rate relative?
A: The equation gives relative rates between gases. Absolute rates depend on additional factors like pressure and temperature.

Q5: What's the fastest effusing gas?
A: Hydrogen (H₂) with MW=2 g/mol, giving a relative rate of ~0.707.