Hello there, I need to compare two atomic masses of elements together. Can I get some help please? Thanks!

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1 Answer
Dec 16, 2017

Answer:

The atomic mass of element A is 1.5 times greater than that of element B

Explanation:

First of all, we know that equal volumes of gases, at the same temperature and pressure contain equal numbers of molecules (Avogadro's hypothesis), so the two gases above have the same number of moles of gas in them.

Since gas A has three times the mass of gas B, it follows that molecules of A have three times the mass of atoms of B.

But since the molecules of A possess two atoms each, the atoms of A must be only 1.5 times more massive than atoms of B.

In other words, the atomic mass of element A is 1.5 times greater than that of element B