Question

How many moles of carbon in 130g of C2H6

Answer 1

 7.22 moles of C2H6. Since there are 2 carbon atoms per C2H6, we must multiply the number of moles of C2H6 by 2 to get the number of moles of Carbon which is 14.4 or 14 if using two sig figs.

Answer 2

C2H6's molar mass is (12+12+6) = 30 grams. if we use stoichiometry we find that
130 grams of C2H6 holds approximately 4.33 moles of the molecule. If we know that there are 2 moles of pure carbon person 1 mole of ethane(C2H6) we can use stoichiometry once more to multiply 2 by 4.33 to find the number of moles of carbon in 130 grams of ethane which is approximately 8.67 moles.