Even in solids there is a small space between the atoms. Depending on how tight the atoms are packed determines the density of matter. This means that a one inch block of wood is not as dense as a one inch block of gold. There is more space between the atoms of the wood than the atoms of the gold.
The total area of Kentucky is 40,409 sq mi (104,659 sq km), of which land makes up 39,669 sq mi (102,743 sq km) and inland water 740 sq mi (1,917 sq km). Kentucky extends about 350 mi (563 km) E-W; its maximum N-S extension is about 175 mi (282 km).
North Korea has a total area listed of 46,528 square miles which is about the size of Pennsylvania. South Korea has a total area listed of 38,622 square miles, which puts it right in between Kentucky (40,409) and Indiana (36,418) in terms of size. Together they are 85,150 square miles. Idaho is 82,747 square miles, so they are a little bigger than Idaho.