Astronomy/gasses

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Expert: - 3/21/2004


Question
Why do heavier molecules, say, carbon dioxide, move more slowly than to the oxygen molecules when they are mixed together?
and
How can a gas can escape from a planet if the average speed of the molecules is less than the escape speed?

Thanks

Answer
Kai,
Simply because they are larger, heavier, and therefore, need more momentum to escape....just as a vaporized carbon tetrachloride {CCl4} molecule would move even more slowly.

#2- Well, as you state....*average* speed, meaning that there will be, at times, some molecules well below average speed, and some, at times, well above average speed.
And if the well above average speed happens to exceed the
bodies escape velocity, then they will escape from the
atmosphere, if they are in a position to do so.
Hope all this helps,
Clear Skies,
Tom Whiting
Erie, PA  USA

Astronomy

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Tom Whiting

Expertise

Astronomy has been my hobby/pasttime for over 50 years.  Currently own 3 telescopes, the largest of which is a 30 inch Newtonian truss Dob that is portable.I taught Astronomy/Meteorology at the University Level for 13 years before retiring in 1995. Being retired and home most of the time, I am able to answer all questions relatively quickly, unless it's a new moon weekend with good observing conditions.  No astrology questions please, or questions about alleged UFO picture identifications.

Experience

Experience: Astronomy has been my hobby and study for over 50 years. We currently now own a 30 inch portable telescope (Updated - Pennsylvania`s largest portable telescope). It can be seen on our website at:http://www.velocity.net/~bwhiting and also attend several regional starparties during the year, and have been on 5 total solar eclipse expeditions.

Organizations: President, Erie County Mobile Observers Group for over 15 years.

Publications: Wrote the "Over Erie Skies" newspaper article in our local newspaper for 11 years (1975-86).

Education: Masters Degree- Taught at the University level for 13 years. Retired 20 years -USAF Pilot - KC-135 with 180 combat missions;  Also Eagle Scout, Philmont staff 2 Yrs, Order of Arrow Lodge Chief, Ham Radio (inactive).

Awards: two discoveries: The mini-coathanger asterism in Ursa Minor (the little dipper) And the mini-ladle- another asterism in the bowl of Ursa Minor. Clients: Currently President of the ECMOG as mentioned above.

Education/Credentials
BS  Metallurgical Engineering Grove City College, PAMaster's Degree, Gannon University, Erie, PA Also retired USAF pilot, 20 years.

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