# Electron configuration

One of the dreams of early chemists was to figure out how to transform lead into gold. Lead has 82 protons in its core whereas gold contains only 79. So conceivably all you’d need to do is remove three protons and presto! So how do you do that? Since protons can’t be stripped off with a chemical reaction, you need to smack it hard with something to knock off just the right amount. Lead, however, if a very stable element, so it’s going to require a lot of energy to remove three protons. How about a linear accelerator?

In a linear accelerator, a charged particle moves through a series of tubes that are charged by electrical and/or magnetic fields. The accelerated particle smacks the target, knocking free protons or neutrons and making a new element (or isotope). Glenn Seaborg (I actually met him!), 1951 Nobel Laureate in Chemistry, actually succeeded in transmuting a tiny quantity of lead into gold in 1980. He actually discovered (or helped discover) 10 elements on the periodic table, 100 new isotopes, and while he was still living (which usually doesn’t happen), they named an element after him (Seaborgium – 106).

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2 Responses to “Electron configuration”
1. Aurora says:

Calcium has 20 electrons, and these fill starting at the lowest possible/available energy before filling higher levels (1s before 2s):

B (Z=5) configuration: 1s2 2s2 2p1
C (Z=6) configuration: 1s2 2s2 2p2
N (Z=7) configuration: 1s2 2s2 2p3
O (Z=8) configuration: 1s2 2s2 2p4
F (Z=9) configuration: 1s2 2s2 2p5

Things start to get a little unexpected as we go higher. For example, 4s is filled before 3d. As the energy of the 3d is higher than 4s, the last two electrons go to 4s, not 3d. It should be 2, 8, 8, 2 and not 2, 8, 10.

Afbau’s principle states that electrons are added to orbitals as protons are added to an atom. When you write down an atom’s configuration, you start with the lowest energy level and add electrons to higher sublevels until you reach the required number of electrons. Energy levels are filled from the bottom up. Beyond the first 20 elements, you need to look at other things that come into play when determining the energy levels/electron placements.

2. joannmiller00 says:

I have a diagram with a Calcium atom diagram and the shells are listed from nucleus to the third shell with the electrons listed in the respective order 2,8,8,2. Is this just unique or was it a typo that should have read the electron numbers: 2,8,10?