想問一個chem既experiment

You may aware that N2 and O2 are the major components of the air. The air composition are as follows:

Nitrogen 78.0842%
Oxygen 20.9463%
Argon 0.93422%
Carbon dioxide 0.03811%
Water vapor about 1%

Since Copper metal will not make any reaction with N2 during heating, it only react with O2 to become CuO and CuO will remain into the central part.

If you push 100cm3 of air using gas syringe to the copper turning, you will find that the resulting volume of the collecting gas syringe will be smaller, it is becuase O2 is reacted with copper. Therefore, the volume difference between the original and the resulting volume is the volume of O2 in the air.

So you can determine the percentage of O2 in air.



Please surf the reference site for the details of this experiment.