Answer:
An electron shell
Explanation:
An electron shell represents the average location of electrons as they travel around an atom's nucleus.
An electron shell may be considered to be the orbit of an electron around the nucleus of an atom.
Electrons orbit around the nucleus of an atom based on their energy levels. The shell closest to the nucleus has the lowest energy level and thus electrons with the lowest energy levels are found in this shell whereas the shell farthest from the nucleus and the electrons occupying these shells have the highest energy levels.
The shell closest to the nucleus is the K shell, followed by L, M, N and so on, having energy levels of 1, 2, 3, 4 and so on.
Each shell can contain only a maximum number of electrons given by the general formula, 2n²; where n is the energy level of the shell. For example, the K shell can hold up to 2(1²) = 2 electrons; the L shell can hold up to eight 2(2²) electrons = 8 electrons.
Each shell consists of one or more subshells, which by themselves also consists of one or more atomic orbitals.
