I need to know the predicted and actual electron configuration for Lanthanum
I know for lets say Cr the predicted config is [Ar] 3d44s2 and the actual is [Ar]3d54s1 but lanthanum is different and i don't know how to do it. Any help?
You can find the actual electron configuration here. Click on element #57 and scroll down the menu on the left side of the page to electron configuration.
http://www.webelements.com/
thank you, do you know what the predicted config would be though?
I was thinking 6s2 4f1
Yes, I believe you are right. According to the mnemonic most of us memorize, 6s fills, then 4f, then 4d.
To determine the predicted electron configuration for Lanthanum, you can use the periodic table and the order in which electron shells and subshells fill.
Lanthanum has an atomic number of 57, which means it has 57 electrons.
First, fill the 1s, 2s, 2p, 3s, and 3p subshells according to the number of electrons they can hold (2 in the s subshell and 6 in the p subshell).
1s2 2s2 2p6 3s2 3p6
Next, fill the 3d subshell. However, in the case of Lanthanum, before filling the 3d subshell, you need to fill the 4f subshell. The 4f subshell can hold up to 14 electrons.
4f14 5s2 5p6 6s2
Finally, after filling the 4f subshell, continue with the other subshells. The next subshell to fill is the 5d subshell.
4f14 5s2 5p6 6s2 5d1
So the predicted electron configuration of Lanthanum would be:
1s2 2s2 2p6 3s2 3p6 4f14 5s2 5p6 6s2 5d1
To find the actual electron configuration of Lanthanum, you can use reliable sources such as the WebElements website mentioned earlier.