# Percentage of water that is void or empty space?

At the atomic level, at sea level on earth, what percentage of normal pure drinking water is void or empty space? What percentage of lead (the kind used to insulate from nuclear radiation) is void or empty space?

-

If you take water and compress it really really hard you can compress it until the nuclei at the centre of the atoms are touching, and at this point the density is about $10^{18}$ kg/m$^3$. Since water normally has a density of $10^{3}$ kg/m$^3$ the compression factor is $10^{15}$, so by this standard an atom is 99.9999999999999% empty space. The trouble is that if you squeeze it even harder you'll find you can squeeze the nuclei into each other and increase the density still further. In fact squeeze hard enough and the atom will turn into a singularity with zero volume. So we'd have to conclude that an atom is 100% empty space.