How often do I need to standardize my titrant?
Naturally, this depends on the stability of the titrant and on what measures have been taken to protect the titrant from the typical contaminants that could cause a reduction in concentration. The most common examples of this titrant protection are the storage of light sensitive titrants in dark bottles e.g. iodine solutions, the protection of Karl Fischer titrants from moisture using e.g. molecular sieve or silica gel, and the protection of certain strong bases e.g. sodium hydroxide, from absorption of carbon dioxide.
