According to the manual, ambient air has CO2 concentrations of about 370
ppm while exhaled air has CO2 concentrations of about 50,000 ppm.
Assuming the increase in CO2 comes about in association with a decrease in
O2, according to a back-of-an-envelope calculation, the increase in
molecular weight (R*rho*T/P) is roughly 2%. Variations about this may be
hard to measure, so I'm not hopeful my suggestion will work. Perhaps it
is easier just to work with germinating peas and see if respiration
results in an increase in solid mass of the peas. This seems like a more
reasonable approach.
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| Robert Cohen Department of Physics |
| East Stroudsburg University |
| bbq@esu.edu East Stroudsburg, PA 18301 |
| http://www.esu.edu/~bbq/ (570) 422-3428 |
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