Question

why do s block elements do not form pseudonoble gas configuration​

Answer 1

Answer:

Explanation:

Transition Metal Ion Formation

Ionic And Metallic Bonding

Transition Metal Ion Formation

Describe the formation of transition metal ions.

Elemental groupings in the periodic table

How do transition metals form ions?

The transition metals are an interesting and challenging group of elements.  They have perplexing  patterns of electron distribution that don’t always follow the electron filling rules.  Predicting how they will form ions is also not always obvious.

Transition Metal Ions

Transition metals belong to the d block, meaning that the d sublevel of electrons is in the process of being filled with up to ten electrons.  Many transition metals cannot lose enough electrons to attain a noble-gas electron configuration.  In addition,  the majority of transition metals are capable of adopting ions with different charges.  Iron, which forms either the Fe 2+ or Fe 3+ ions, loses electrons as shown below.

& text{Fe} quad qquad rightarrow quad text{Fe}^{2+} quad + quad 2text{e}^-\& [text{Ar}]3d^64s^2 quad quad [text{Ar}]3d^6\& text{Fe} quad qquad rightarrow quad text{Fe}^{3+} quad + quad 3text{e}^-\& [text{Ar}]3d^64s^2 quad quad [text{Ar}]3d^5

According to the Aufbau process, the electrons fill the 4 s sublevel before beginning to fill the 3 d sublevel.  However, the outermost s electrons are always the first to be removed in the process of forming transition metal cations.  Because most transition metals have two valence electrons, the charge of 2+ is a very common one for their ions.  This is the case for iron above.  A half-filled dsublevel ( d 5 ) is particularly stable, which is the result of an iron atom losing a third electron.