Answer:
d. 127 g/mol.
Explanation:
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In this case, since we have the amount of molecules of this this compound, we are able to compute the moles out there by using the Avogadro's number:
Which correspond to the moles of X2. Then, by using the mass we are able to compute the molar mass of X2:
It means that the atomic mass of X halves the molar mass of X2, which is then d. 127 g/mol.
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