When you placed transition metals on a scale to find their mass, why are the values negative or positive. For example these compounds
Cobalt (II) chloride
Copper (II) chloride
Iron (II) chloride
Manganese (II)
chloride
Nickel (II) chloride
Zinc chloride
These all resulted in a positive or negative value. Does it have anything to do with how you place these metals. This all deals with paramagnetism and diamagnestism but I don't really understand how.
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First off I think it is important for you to realize that you are not using (or thinking about) an ordinary balance. This mass measurement must be used in conjunction with an externally applied magnetic field. If the element has unpaired electrons it is paramagnetic and will be attracted into the magnetic field and if it is diamagnetic (no unpaired electrons) it will be repelled by the external magnetic field. Transition metals are the most often used examples of this behavior because they have incomplete 3d orbitals. CoCl2, for example, has a 1s2 2s2 2p6 3s2 3p6 3d7 electron configuration for the Co^2+ ion. Since the d orbital has 5 "boxes" in which to put the 7 electrons, 5 electrons can be used to place 1 electron in each box. That leave 2 electrons to be used to "pair up" with electrons already there in the first two boxes and that leaves 3 boxes with just one electrons each so there are 3 unpaired electrons. Zn has zero, Mn(II) has 5 unpaired, etc.
1 answer