* Gordon wrote, On 6/21/2007 6:48 PM:
If you have to wear an oxygen mask at high altitudes because oxygen
(32) is heavier than other gases that make up our air (28),

And what makes you think this is true? The concentration of oxygen
remain essentially unchanged with altitude, at about 21%.

then how
does co2 get into the stratosphere and cause a warming blanket when co2
(44) is much heavier than oxygen?
Gordon