9/14/2014
ALEKS Alex H. Yuan - 09/14/2014 5:56:03 PM EDT - Copyright © 2014 UC Regents and ALEKS Corporation
Alex H. Yuan - 09/14/2014 5:56:03 PM EDT
General Chemistry (First Semester) / Chem 110 FA 2014 – CH110 FA14 S25-36 (Dr.
Barber)
1.
Understanding the exceptional electron configurations in the first transition
series
In Universe recently discovered by an intrepid team of chemists who also happen to
have studied interdimensional travel, quantum mechanics works just as it does in our
universe, except that there are six orbitals instead of the usual number we observe
here.
Use these facts to write the ground-state electron configurations of the eleventh and
twelfth elements in the first transition series in Universe
Note: you may use
to stand for the electron configuration of the noble gas at the
end of the row before the first transition series.
eleventh transition metal:
twelfth transition metal:
You can solve this problem using some of the many connections between the Periodic
Table and the electronic structure of atoms, and by the fact from quantum mechanics that
exactly half filled subshells have unusual stability.
First, let's use the fact that the width of the blocks in the Periodic Table is equal to the
number of electrons that fit into the corresponding subshell. Since
instead of
electrons fit into each subshell, the block in Universe will be twelve instead of ten
elements wide:
https://secure.aleks.com/alekscgi/x/Isl.exe/1o_u-IgNsIkr7j8P3jH-lJiYsPgPQIfQokR4hWMNIe-wKsFh3XosSLHEgiSbeyaRdtEEkEkQXWQnynL87sp-B_…
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9/14/2014
ALEKS Alex H. Yuan - 09/14/2014 5:56:03 PM EDT - Copyright © 2014 UC Regents and ALEKS Corporation
1
1
2
3
2
4
5
3 11 12
6
7
8
9 10
13 14 15 16 17 18
4 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
5 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
You can see the eleventh and twelfth elements in the first transition series are elements
and
We can build the electron configurations for neutral atoms of those elements
by using the simple aufbau method:
Element
Element
Here
stands for the electron configuration of
the noble gas at the end of Period
Are these the answers? Not quite. Notice that Element
transition series of Universe
has all
and consequently the
is at the very end of the first
subshell in its atoms is filled (it
of the electrons it can hold).
In our universe, copper (
), the element just before the end (
series, has an unusual electron configuration:
The electron configuration of
) in the first transition
differs from what the simple aufbau method would
predict: one electron has been moved from the
to the
subshell. This makes the
subshell filled, which quantum mechanics tells us is an unusually stable arrangement.
There's no reason to think the same effect won't operate in Universe
most likely electron configuration for Element
subshell, to make it filled.
Note: in our universe, an exactly half-filled
in mind for variations on this question.
has one
That means the
electron moved down to the
subshell also has unusual stability. Keep this
https://secure.aleks.com/alekscgi/x/Isl.exe/1o_u-IgNsIkr7j8P3jH-lJiYsPgPQIfQokR4hWMNIe-wKsFh3XosSLHEgiSbeyaRdtEEkEkQXWQnynL87sp-B_…
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9/14/2014
ALEKS Alex H. Yuan - 09/14/2014 5:56:03 PM EDT - Copyright © 2014 UC Regents and ALEKS Corporation
eleventh transition metal:
twelfth transition metal:
Copyright © 2014 UC Regents and ALEKS Corporation
https://secure.aleks.com/alekscgi/x/Isl.exe/1o_u-IgNsIkr7j8P3jH-lJiYsPgPQIfQokR4hWMNIe-wKsFh3XosSLHEgiSbeyaRdtEEkEkQXWQnynL87sp-B_…
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