Understanding electronic configuration

I don't really understand this electronic configuration of a thing. Suppose I want show the electronic configuration of calcium, how do I show it? Is like this

1. 2, 8, 8, 2 or
2. $$1s^22s^22p^63s^23p^64s^2$$

#2 is the winner!

chemisttree said:

#2 is the winner!

What then do we call #1?

I don't think it has a special name. Yes, it is a correct number of electrons on each shell, but it is filling of subshells that is much more important for chemical properties. That's why we prefer #2, as it tells as much more.

And yes, thanks to Aufbau principle they are to some degree equivalent.

Borek said:

I don't think it has a special name. Yes, it is a correct number of electrons on each shell, but it is filling of subshells that is much more important for chemical properties. That's why we prefer #2, as it tells as much more.

And yes, thanks to Aufbau principle they are to some degree equivalent.

Why then is the filling of subshell much more important for chemical properties?

You must represent it as in 2. for generality. The Madelung ordering principle has exceptions within the transition metals.

Chijioke said:

Why then is the filling of subshell much more important for chemical properties?

Because it tells you which orbitals the valence electrons are in, and they are the most important electrons to understand things like the spectrum of atoms and chemical reactivity.

Chijioke said:

Why then is the filling of subshell much more important for chemical properties?

In a way the only answer you can get is: because that's the way it is.

We don't create these rules, we observe reality and we try to understand and describe it. Sometimes we can - after creating a model of how something works - try to rationalize observed effects and rules and explain them in terms of for example energies involved, but it is not that these rationalizations are the "real" thing. The only real thing is - no pun intended - the observed reality.

Thatdburownnotationknownonly2u

That would be your own notation known only to you. We also have syntax rules for language and agreed upon spellings for words. It conveys better information in a clearer manner.