How many carbon atoms are contained in 5.50g of C2H6?

Question

i also have one that says: How many grams of Iron (Fe) are contained in 15.8g of Fe(OH)3?

are they worked the same? if so, can someone please explain how to work either of them for me? thanks!

Answer 1

the answer is 2.2084333*10^23 its 2.208433 multiplyed by 10 to the power of 23

                 the procedure is

                     first caluculate the molar weight of C2H6

                            2 C=24  + 6 H=6 so total weight is 30

              so in 30 gms we have avagadro number of molecules and each molec has two C atoms

                              avagadro number is 6.023*10^23

                        so for

                               30 gms it has 2*avgadronumber of C atoms  

                          the number of atoms of C in 5.50gm is

                              5.50*2*6.023*10^23/30=2.084333*100000000...