Question

How many moles are in `4.21 x 10^22` molecules of `SO_3`?

Answer 1

Well a molar quantity specifies `6.022xx10^23` individual items of stuff..........

Explanation:

And so we take the quotient...........

`(4.21xx10^22*"molecules")/(6.022xx10^23*"molecules"*mol^-1)`

`=0.0700*mol`, and thus there `0.0700` moles of `SO_3`, `0.0700` moles of `"S atoms"`, and `0.210` moles of `"oxygen atoms"`.