This is a my sandbox.

At present I'm drafting a section for chemical symbol.

Each element symbol can have leading and trailing codes, e.g.

${\displaystyle {}_{d}^{c}\!Ab_{f}^{e}}$

Here the element's symbol is Ab. This is fictional element.

• On the left are the element's nuclear properties.
  • c indicates the atomic mass number, and thus which isotope of the element is involved.
  • d indicates the atomic number . The atomic number is fixed for each element, and is thus rarely given, except in introductory texts, where the reader is not excepted to know the atomic number for each element.

• On the right are the element's chemical properties.
  • e indicates the electric charge on element. It is shown as number followed by either a plus or a minus. However, the number 1 is frequently omitted. A negative charge indicates that the element has an extra electron, a positive charge that the element has lost an electron. If completely omitted then the element has no charge.
  • f indicates the count of each element in the molecule . If omitted then there is 1 of the element in the molecule.

Normally only nuclear or chemical properties are given - only with the lightest elements does the atomic mass affect chemical reactions.

For ionic groups the charge may refer to the group, and not each element e.g. ${\displaystyle {}H_{2}^{+}{}NO_{3}^{2-}}$, for formula for nitric acid, has two hydrogen atoms, both with a positive one charge, and one NO₃ nitric group, which has a negative two charge.