chem(6)自學 - Long Question

3)
Air can be dissolved in water. The dissolved air can be driven out for collection using a special set-up. In an experiment, 50 cm^3 of such dissolved air had been collected. The dissolved air was passed backand forth over some heated copper turings. Afterwards, the volume of dissolved air left was 33cm^3.

b)
Which gas in air did react with the heated copper turning??

c)
Write a word equation between answer in (b) and copper.

d)
What volume of this gas was present in 50 cm^3 of dissolved water??

e)
Calculate the approximate percentage of this gas in dissoved air.

f)
What is the percentage of this gas in the atmosphere??

g)
Suggest a reason for the difference between the answers in (e) and (f).