After several months of development we'd like to present the ultimate tool for predicting ground state electron configurations of atoms in almost any oxidation state - Electron Config Pro (link at the bottom of the page).
Electron configurations are taught at various levels of education. Possibly the first instance of a student being introduced to the atomic electron configurations is in high school, but the knowledge is revised and updated at all university-level science and technology courses. There is literally not a single science course where introductory chemistry is not a requirement, and many students fail to understand how electron configurations work or how to write them. Furthermore, many students who think that they've understood it still end up making mistakes when it comes to tests and exercises. Fear no more.
In this app we present the theory in a way that should be easy to comprehend at any educational level where electron configurations are taught, and mostly because we've tried to explain not only the hows, but also the whys. We call our theory a summary, but it really contains a very large amount of information that discusses a lot of physics and chemistry of the atom. And when we say large, we mean over 8000 words, or roughly 10-11 pages.
But that's just the theory. Everyone can find the very same theory in their books and on the internet; we just included it for convenience. What really separates our app from the rest is that it is an interactive, dynamic electron configurations engine that is capable of calculating almost any desired electron configuration. By going through a list of elements and then playing with the add/remove electron buttons (which are called Oxidise and Reduce!), students can learn how the configurations change almost as if by performing an actual experiment! Our engine incorporates the Aufbau principle, which incorporates the Pauli exclusion principle, Hund's rules and the Madelung-Klechkowskii rule, but also the exceptions to the Madelung-Klechkowskii rules which were determined experimentally!
In addition, we also include exercises where students can test their electron configuration writing skills by attempting to write electron configurations for some random atoms in some random oxidation states. Yes, this means there is literally an unlimited supply of questions! We include some other perks with the app, but it's best if you head over there to see the screenshots for yourself!