VARRRRRRRRRIABLE VALENCYYYYYYYY !?!?!?!?!?!?!?!?!?!?!?!?
 

:shock: :?: How can elements have variable valency? :?: :shock:

:!: An example is of iron. In this forum only, it is given that it can have max. oxidation no. "3" as in Fe2O3. But how can it be possible as its electronic config. is Fe(2,8,14,2) :?: As per my knowledge, substances react to get noble gas config :!: :!: :!:

Elements don't always react to make noble gas configurations.

On one hand, the atomic system is a highly charged nucleus swarming with surrounding electrons, violently attracted toward it.

On the Other hand, those electrons obey rules modeled by quatum mechanics.

All kinds of stable configurations can exist - and even some unstable ones.

Too bad we can't take a snapshot!