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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Craftylikeafly on October 26, 2009, 12:08:20 PM

Title: Condensed electron configurations
Post by: Craftylikeafly on October 26, 2009, 12:08:20 PM

Write the condensed electron configurations for the Ga atom.

Ex: [He] 2s^22p^2

im having trouble understanding why in the example the, [He] they have in brackets, why did they put that there?
i know the answer to the problem is [Ar]4s^23d^104p^1, so i have the same problem, why do they put a [Ar] there in front?

my work:

Ga electron configuration
1s^1s^22p^63s^23p^64s^23d^104p^1

Title: Re: Condensed electron configurations
Post by: Borek on October 26, 2009, 12:22:03 PM

[He] is a shortcut to noble gas configuration "core" that sits inside the element. Lithium can be written as 1s²2s¹, or [He]s¹, sodium is either 1s²2s²2p⁶3s¹ or [Ne]3s¹ and so on.

And you answer starts with an error...