The following is the introduction to a special e-publication called Determining the Age of the Earth (click the link to see a table of contents). Published earlier this year, the collection draws articles from the archives of Scientific American. In the collection, this introduction appears with the title, “Stumbling Toward an Understanding of Geologic Timescales.”
Answer:
carbon dioxide is a gas so it isn't collected over water.
Explanation:
it works for insoluble gases such as hydrogen,or gases that do not dissolve easily in water such as ammonia and chlorine are readily soluble in water and are not collected this way.
hope it is helpful for you.
Atomic mass is the answer
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