Now #N_A=6.022xx10^23*"molecules"#. This specifies a molar quantity of stuff. By definition #N_A# #""^12C# ATOMS has a mass of #12.00*g#, and constitutes a molar quantity. The #"mole"# is thus the link between the sub-micro world of atoms and molecules, which we cannot see but whose existence we can infer, to the macro world of #"grams"#, and #"litres"#, that which we can measure out on a balance or measure volumetrically.
Molar masses are conveniently printed on the Periodic Table. You will not have to remember the masses, but you will have to use the Periodic Table to express molar masses of different compounds. Molar quantities of carbon and oxygen atoms have masses of #12*g#, and #16*g# respectively. You have #44.0*g# of carbon dioxide. It does not take too much arithmetic to work out that such a mass represents a molar quantity of carbon dioxide molecules...........
And thus there are #6.022xx10^23# individual carbon dioxide molecules (or #N_A# such #"mollykewels"#). In this quantity, can you tell how many carbon and oxygen atoms there are?
