Atoms aren’t just small: they’re really really small.
10^23 is an astonishingly large number. The number of grains of sand in all the beaches in the world is around 10^18. The number of stars in our galaxy is about 10^11. The number of stars in the entire visible Universe is probably around 10^22. And yet the
number of water molecules in a cup of tea is more than 10^23.