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astha

What is inert pair effect?

In trimethyl amine nitrogen has pyramidal geometry whereas whereas in trisilylamineN(SiH₃)₃ it has a planar geometry. Why?

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Refer to the post below:

http://www.goiit.com/posts/list/3729.htm

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Removing the question from the pending queue, there is no response from the post owner.

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taruntanuj007

See Inert Pair Effect is that as we go down a group the +2 oxidation state is stabler than the higher oxidation state

eg PbCl2 is stabler then PbCl4

And N(SiH3)3 is planar becoz Si has empty 3d orbital so lp of Nitrogen enters that d orbital and makes it planar that's why N(ch3)3 is stronger base since lp is not delocalised but in N(SiH3)3 it is

001sri

in the higher atomic number elements the electrons are not shielded effectively due to lower shielding power of f atomic orbitals.
due to this the s electrons r strongly attracted to the nucleus as compared to other electrons.
thus these electrons become inert .

DON007

all r not absolutely right .........................

now look,

1) inert pair effect is reluctance of ELECTRONS of s orbital to move out of the shell ,

this is because of 2 options :

a) s orbitals is very close to nucleus and therefore due to higher coulombic charge , they r very difficult to remove

b) higher SCREENING EFFECT CAUSED BY Selectrons than others

( understood)

2)

N(SiH3)3 is planar because SI IS PRESENT IN SECOND PERIOD , THEREFORE IT HAS D ORBITALS LEFT AND THEREFORE

LONE PAIR OF N2 r transferred to Si,

therefore planar

but in N(ch3)3 u know CARBON HAS NO D-ORBITALS LEFT...........................THERFORE PYRAMIDAL ...............

NOW U SHOULD HAVE UNDERSTOOD ..

THANKU

anirudhavasarala

Is Si (Silicon) present in the 2nd period?!!

chimanshu_007

no Si is in 3rd period , C is in 2nd period

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