The statement that atoms are mostly empty space refers to the fact that the volume occupied by the nucleus and electrons within an atom is extremely small compared to the total volume of the atom. The nucleus, which contains protons and neutrons, is located at the center of the atom and accounts for most of its mass. The electrons, on the other hand, occupy regions around the nucleus in specific energy levels or orbitals.
While it is true that the space between the nucleus and electrons is relatively large compared to their sizes, it is important to note that the concept of "shrinking" an atom can be misleading. Atoms are governed by quantum mechanics, and their properties, including size, are determined by the arrangement and behavior of their constituent particles.
In quantum mechanics, particles such as electrons do not behave like classical objects with well-defined positions. Instead, they are described by wave functions, which represent the probability distribution of finding the electron at a particular location. The size of an atom is typically defined by the spatial extent of the electron cloud.
Attempting to "shrink" an atom by compressing the electron cloud would require overcoming the electromagnetic repulsion between electrons, which is governed by the laws of quantum mechanics. These repulsive forces prevent electrons from collapsing into the nucleus. Moreover, trying to compress an atom to a smaller volume would result in an increase in the energy of the system, as electrons would occupy higher energy levels or orbitals, leading to an unstable configuration.
In summary, while atoms may be considered mostly empty space in terms of the volume occupied by the nucleus and electrons, the concept of physically shrinking an atom is not applicable in the context of quantum mechanics. The size and structure of atoms are determined by the principles of quantum mechanics and the behavior of their constituent particles.