Discussion on MAGNETIC properties of metal
Iron has unpaired electrons and it is attracted by magnet
Sodium and potassium have unpaired electrons but why they are not attracted by magnet
........
I have guessed a reason but I am not sure whether I am right or wrong
Let us start OUR discussion
1
VALENCE electrons of a metal that we see in electronic configuration do not stay with the atom of metal.
2
Metal is a collection of positive charged ions surrounded by a sea of free electrons
3
Electronic configuration of iron is 4s2 , 3d6
Crystal of iron is a collection of ions with Electronic configuration 3s2, 3d6
In this ion 3d has 4 unpaired electrons
This could be the reason for iron to be attracted towards magnet
4
Electronic configuration of sodium is 3s1, 2p6
Crystal of sodium is a collection of ions with Electronic configuration 2s2, 2p6
THIS ion does NOT have unpaired electrons
This could be the reason for sodium to NOT get attracted towards magnet.
SHANTANU AGRAWAL
. ...........
You are almost correct. The only thing iron has a special characteristics that its ions align their magnetic moments with neighbours. The attraction that we generally see between iron pieces and magnet is due to this "ferromagnetic" character.
Unpaired or paired electrons give dia and para magnetism. The attraction etc is too weak to be observed in normal set ups.
Good thinking.
Best wishes.
Harish
www.hcverma.in
Ex-Professor of Physics
IIT Kanpur
1
www.hcverma.in
2
www.facebook.com/hcvermaphysics
3
https://www.youtube.com/channel/UCST7O07V0HwBkK_wCB6EB5g
.............
Don't know who I am communicating with. But anyways.
Magnetism in most metals is not seen this way. Check out Pauli's
paramagnetism. In the free electron bands, the up and down spins cancel
and there is no permanent magnetism. Only in a field, the bands move and
unbalanced spin is caused, leading to small value of magnetism, this is
para magnetic behavior.
Some metals, however, are different. Like, Fe, Co, Ni....their magnetic
properties need to be described through quantum mechanical exchange
integral...there is no other way to understand the phenomena. This
exchange integral decides how spins on atoms in a crystal arrange
themselves. Accordingly the total spin will manifest, and even in
absence of a field, you will have residual magnetism.
hope this helps.
Deepak
Professor
Materials Science and Engineering
& National Center for Flexible Electronics (FlexE)
Indian Institute of Technology
Kanpur 208016, India
Sodium and potassium have unpaired electrons but why they are not attracted by magnet
........
I have guessed a reason but I am not sure whether I am right or wrong
Let us start OUR discussion
1
VALENCE electrons of a metal that we see in electronic configuration do not stay with the atom of metal.
2
Metal is a collection of positive charged ions surrounded by a sea of free electrons
3
Electronic configuration of iron is 4s2 , 3d6
Crystal of iron is a collection of ions with Electronic configuration 3s2, 3d6
In this ion 3d has 4 unpaired electrons
This could be the reason for iron to be attracted towards magnet
4
Electronic configuration of sodium is 3s1, 2p6
Crystal of sodium is a collection of ions with Electronic configuration 2s2, 2p6
THIS ion does NOT have unpaired electrons
This could be the reason for sodium to NOT get attracted towards magnet.
SHANTANU AGRAWAL
. ...........
You are almost correct. The only thing iron has a special characteristics that its ions align their magnetic moments with neighbours. The attraction that we generally see between iron pieces and magnet is due to this "ferromagnetic" character.
Unpaired or paired electrons give dia and para magnetism. The attraction etc is too weak to be observed in normal set ups.
Good thinking.
Best wishes.
Harish
www.hcverma.in
Ex-Professor of Physics
IIT Kanpur
1
www.hcverma.in
2
www.facebook.com/hcvermaphysics
3
https://www.youtube.com/channel/UCST7O07V0HwBkK_wCB6EB5g
.............
Don't know who I am communicating with. But anyways.
Magnetism in most metals is not seen this way. Check out Pauli's
paramagnetism. In the free electron bands, the up and down spins cancel
and there is no permanent magnetism. Only in a field, the bands move and
unbalanced spin is caused, leading to small value of magnetism, this is
para magnetic behavior.
Some metals, however, are different. Like, Fe, Co, Ni....their magnetic
properties need to be described through quantum mechanical exchange
integral...there is no other way to understand the phenomena. This
exchange integral decides how spins on atoms in a crystal arrange
themselves. Accordingly the total spin will manifest, and even in
absence of a field, you will have residual magnetism.
hope this helps.
Deepak
Professor
Materials Science and Engineering
& National Center for Flexible Electronics (FlexE)
Indian Institute of Technology
Kanpur 208016, India
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