Question

109.4g Mg contains how many moles?

Answer 1

Answer:

Well, what is the atomic mass of magnesium metal?

Explanation:

Is it not 24.31⋅g⋅mol−1. How did I know this? Did I know the mass from the top of my head?

And so we take the quotient, Mass of stuffmolar mass of stuff

≡109.4⋅g24.31⋅g⋅mol−1=4.50⋅11mol=4.50⋅mol