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kiteidolized
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Help me!

Post by kiteidolized »

I am having a really hard time understanding the concept of isoelectronic . If anyone could help me that would be awesome!

NH4+ is isoelectronic with (NH3, NO3-, AlCl4-, AlCl3)

Al3+ is not isoelectronic with (Na, F, Ca2, Mg2)
Last edited by kiteidolized on Tue Mar 25, 2025 12:48 am, edited 2 times in total.
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ChenBeier
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Re: Help me!

Post by ChenBeier »

Ammonium NH4+ is normally isoelectronic with BH4- and CH4. Same orbital sp3 configuration.
What fits here would be only AlCl4- , but it's in 3 periode.

Al 3+ is not isoelectronic with (Na, F, Ca2, Mg2),

Makes no sense because Ca2 and Mg2 not existing, or do you mean Mg 2+ and Ca 2+. The same for Na and F, Na+ and F- is existing and isoelectronic.

Al 3+ and Mg 2+ fits each other.
Thiandes
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Re: Help me!

Post by Thiandes »

geometry dash spamNH4⁺ is isoelectronic with NH3 because both have 10 electrons.
Al³⁺ is not isoelectronic with Ca²⁺ since Al³⁺ has 10 electrons and Ca²⁺ has 18.
But now I’m wondering — why is NH4⁺ isoelectronic with NH3 even though one is a cation and the other is neutral?
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ChenBeier
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Re: Help me!

Post by ChenBeier »

NH3 and NH4 + are isoelectronic. If you get ripped off the H, then N 3- will be remain in both cases.

NH3 => 3 H+ + N 3-

NH4+ => 4 H+ + N 3-


BH4-, CH4 and NH4+ are also isoelectronic. The amount of electrons 10 are the same.


https://slideplayer.com/slide/5247022/1 ... pecies.jpg

Al 3+ And Mg 2+ can be compared.

Other examples

https://search-static.byjusweb.com/ques ... 760f4c.jpg
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