During an effusion experiment, a certain number of moles of an unknown gas passed through a tiny hole in 50 seconds. Under the same conditions, the same number of moles of oxygen gas passes through the hole in 30 seconds. What is the molar mass of the unknown gas?

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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