Welcome to Westonci.ca, the ultimate question and answer platform. Get expert answers to your questions quickly and accurately. Connect with a community of experts ready to help you find solutions to your questions quickly and accurately. Explore comprehensive solutions to your questions from knowledgeable professionals across various fields on our platform.

A turbo molecular pump has rapidly rotating blades which hit the molecules of gas in the coating chamber. This collision transfers some momentum to the particles. This process of momentum transfer is more efficient if the average linear velocity of a molecule is less than the linear velocity of the blade tip. Assuming that a particular pump has a linear blade tip velocity of 400 m/s, (a) calculate the ratio of the average room temperature (say, 27 0 C) molecular velocity to blade tip velocity for the gases such as hydrogen, nitrogen and xenon having molar masses of 2, 28 and 131 g/mol, respectively. (b) Is the turbo molecular pump better for pumping heavy element or light element?

Sagot :

Answer:

heavy molecules are pumped much more efficiently than light molecules. Most gases are heavy enough to be well pumped but it is difficult to pump hydrogen and helium efficiently.