The ground (normal) state of an atom has the lowest possible energy with oppositely-charged particles being as close as possible.
What is the maximum number of electrons in each energy level (shell)?
The maximum number of electrons in various energy levels (shells) for the first twenty elements is given below:
Energy level 1 (shell 1): 2 electrons
Energy level 2 (shell 2): 8 electrons
Energy level 3 (shell 3): 8 electrons
Energy level 4 (shell 4): 2 electrons
Energy level 2 (shell 2): 8 electrons
Energy level 3 (shell 3): 8 electrons
Energy level 4 (shell 4): 2 electrons
two electrons are 1 and 2
(as shown for the beryllium atom at the right).
ten electrons are 1, 2 and 3.
eighteen electrons are 1, 2, 3 and 4.
(as shown for the beryllium atom at the right).
ten electrons are 1, 2 and 3.
eighteen electrons are 1, 2, 3 and 4.
The lines represent energy levels, not paths!
While we know the exact energy of the electron, we do not know its exact path, but electrons having higher energies are found on average farther from the nucleus.