Which of the following has the largest number of oxygen atoms?

#a)# #3.65 xx 10^20# molecules of #"SO"_2#
#b)# #3.65 xx 10^20# molecules of #"SO"_3#
#c)# #"0.0553 g SO"_3#
#d)# #5.06 xx 10^(-3) "mols SO"_3#

1 Answer

Answer:

The biggest amount of oxygen is in #"5,06" × 10^"-3"# mol.

Explanation:

Since a mol is #6,02 xx 10^23# molecules, you have #(3,65 xx 10^20)/ (6,02 xx 10^23)= 6,06 xx 10 ^(-4) # mol each of #SO_2# and #SO_3#.

Obviously, there are more oxygen atoms in #SO_3#.

Furthermore, since the MM of #SO_3# is 80.1 g/mol you have #(0,0553 g)/(80.1 g/(mol)) = 6,90 xx 10^(-4) mol SO_3#.

Then, the bigger amount of oxygen is in the 0,0553 g of #SO_3# where there is a bigger number of moles.

And #"5,06" × 10^"-3"# mol of #SO_3# contains even more moles than 0,0553 g of #SO_3#.