Question

How many atoms are in 1.75 moles of zinc?

Answer 1

How many atoms in `1.5` `"dozen"` zinc atoms? Clearly, there are `18`.

Explanation:

We know that `1` `mol` of stuff specifies `"Avogadro's Number, "N_A` individual items of stuff. Avogadro's Number `=` `6.022xx10^23*mol^-1`.

So you have `1.75xxN_A` atoms of zinc. You do the arithmetic, and tell us what is the mass of this quantity, this number, of zinc atoms?

The use of `"Avogadro's number"` as we use any other collective number, e.g. score, dozen, gross, is entirely legitimate. Why do use such an absurdly large number? It turns out that `N_A` `""^1H` atoms have a mass of `1*g` precisely. `"Avogadro's number"` is thus the link between atoms and molecules, the which we can't see, to the macro world of grams and litres, that which we can conveniently measure in the laboratory.