I hope not sick of spending a ton of money to see them play a short set <| sep |> Same discussion every damn time . It ' s getting quite boring . Just ignore the memepool . <| sep |> Iron 56 , which is the most common isotope of iron , weighs 55 . 935 grams per mol . A mol , of course , is 6 . 0221023 atoms . If both blocks are exactly the same dimensions , and they ' re both made of Iron 56 , then in theory they ' d have exactly the same number of atoms because if they ' re exactly the same dimensions , they ' ll have exactly the same mass , and if they ' re exactly the same mass , they ' ll have exactly the same number of atoms . In practical terms , two blocks of the same dimensions will not be exactly the same . But hypothetically , yes , there ' s a direct relationship between the mass of something , and how many atoms of that something there are .