Someone please solve this question??

Question

Consider a 6.66 g sample of C2H2. How many atoms of C would be in this sample? Report your answer with 3 significant figures and in scientific notation. Use * for the multiplication symbol.

Answer 1

To figure atoms, we need to know moles.

6.66 g C₂H₂ / 26.04 g/mol = 0.256 moles C₂H₂

If we know there are 6.02*10²³ atoms in every mole, there are

0.256 * 6.02 * 10²³ = 1.54*10²³ molecules C₂H₂.

HOWEVER, they don't want the whole compound - they want just carbon. We know how many molecules we have, and there are two carbons per molecule, which means we must double our answer:

1.54*10²³ * 2 = 3.08*10²³ atoms C