If you removed all empty space from atoms, all of humanity would fit in a sugar cube
Atoms are almost entirely empty space. The nucleus of an atom occupies roughly 0.0001% of the atom's volume — the rest is the electron cloud. If you could compress all of humanity's 8 billion people by removing the empty space between subatomic particles, the resulting mass of pure matter would fit in a volume smaller than a sugar cube. The cube would weigh about 5.5 billion tonnes — approximately the weight of a mountain.
Everything you see — every building, every mountain, every ocean, every person — is almost entirely empty space. Matter as we experience it is mostly the electromagnetic forces between near-vacuum particles.
“Remove the empty space from atoms and all of humanity would fit in a sugar cube. That cube would weigh 5.5 billion tonnes.”