woelen
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Fun experiment with magnet and ferrosic salts
I did an experiment in which some magnetite precipitate is formed and moved it around with a medium strength neodymium magnet (which is still very
very strong compared to normal old-fashioned nagnets).
http://woelen.homescience.net/science/chem/exps/magnetite/in...
I just post this for the fun of it. Try it if you have the materials, only very basic chemicals and equipment are needed.
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blogfast25
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Oh, the Internet is full of ferrofluid experiments and recipes. Transfer the magnetite with the help of oleic acid into a non-aqueous solvent (I used
kerosene) and make it dance to your neodymium magnet.
See e.g.:
http://www.sci-spot.com/Chemistry/liqimag.htm
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Jor
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Seems like a lot of iron-salts are actually magnetic. I once decomposed ferrous oxalate, and threw the pyrophoric iron out of the test tube. It
ignited, leaving a dark red powder, wich is iron(III)oxide. This is also magnetic.
Very nice experiment!
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JohnWW
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High-spin Fe compounds, especially of Fe(III) with the maximum possible 5 unpaired d electrons of a 3d (5 orbitals) transition metal, and with some of
these in the conduction band (metal-metal bonding), are generally ferromagnetic. Compounds of Fe(III) other than these are those with strong cationic
complexing ligands, such as amines, cyanide and halides, in which spin-pairing of 3d electrons is forced so as to allow some donated electron pairs
to enter 3d orbitals, in addition to some of the donated electron pairs also occupying vacant 4s and 4p orbitals, with low net electron spins as the
result. This also applies to Co(IV) compounds, which are also often ferromagnetic, but not to Mn(II) or Cr(I) compounds because the spin orientation
of the unpaired 3d electrons in them is antiferromagnetic. The electronic symmetry of Fe(III) and Mn(II) and Co(IV) (and Ni(V) if it can be obtained),
with 5 unpaired d electrons, one in each orbital, gives these oxidation states more stability than would be expected purely from ionization
potentials.
The same applies to other d series metals; and to the middle of the rare earth series, in which having 7 unpaired 4f electrons, one in each orbital,
is a stabilizing influence (enabling (II) and (IV) oxidation states either side of it, as well as (III)), besides producing very strong
ferromagnetism.
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MJ_
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Thanks for this woelen I will give this a try when i get some time. I have tried some of your other experiments on your website and found them very
easy to follow and well thought out, thanks for your contribution.
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halogenstruck
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when any kind of iron oxide is heating in hi temperatures over 900'c in air,most of it convert to most stable form at this temperature ,Fe3O4 which
is magnetic and also conductor.even Fe3O4 is used as anode as it conducts electricity!!
Quote: Originally posted by Jor  | I once decomposed ferrous oxalate, and threw the pyrophoric iron out of the test tube. It ignited, leaving a dark red powder, wich is iron(III)oxide.
This is also magnetic.
rquote]
[Edited on 20-10-2009 by halogenstruck]
[Edited on 20-10-2009 by halogenstruck] |
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