Final answer:
An orbital filling diagram is a visual representation of the arrangement of electrons in an atom. The order of filling subshells follows a specific pattern based on the atomic number. Different methods and mnemonic devices can be used to remember the order of filling electrons in larger atoms.
Step-by-step explanation:
An orbital filling diagram is a visual representation of the arrangement of electrons in an atom. Each sublevel is labeled by its principal energy level and sublevel, and the individual orbitals are shown as circles or squares. Electrons are represented by arrows inside the circles, where an upward arrow indicates one spin direction and a downward arrow indicates the other direction.
The order of filling the subshells follows a specific pattern. The filling order starts from hydrogen and includes each subshell in increasing order of Z (atomic number). For example, after filling the 3p block, the next orbital to be filled is the 4s, followed by the 3d orbitals.
There are different ways to represent the order of filling electrons, such as the arrows passing through subshells in the appropriate filling order. A helpful mnemonic device is to follow the arrows in figure 8.4.1, which pass through the subshells in the order they are filled in larger atoms.