Question

You need 2.5 moles of aluminum for an experiment. How many atoms of aluminum is this?

Answer 1

`2.5 xx N_A`, where `N_A` is Avogadro's number, `6.02214 xx 10^23`.

Explanation:

`N_A` is simply a number, admittedly a very large number. When I have such a number of any element/molecule I have an equivalent mass, and an equivalent number of atoms or molecules. When I have such a number of `Al` atoms, I have a mass of `26.98` `g` of `Al`. You have two and a half times this number of `Al` atoms. What is the mass of your aluminum??