|MadSci Network: Chemistry|
No, mercury can't be magnetized. For one thing, it's a liquid at room temperature; for the other, even if you lowered the temperature to the point that mercury is a solid, it is not ferromagnetic.
Atoms typically have what is called a magnetic moment, which you can think of as a magnetic arrow pointing in a particular direction; this is analogous to a bar magnet, with a north pole and a south pole. In most substances the atoms have weak magnetic moments, but in others the magnetic moments are quite strong.
Magnetization is what we call a bulk property, that is, it is a property which appears only when you have many atoms together. In order for a substance to be magnetized, the atoms in it must line up so that their magnetic moments point in the same direction. In a liquid, atoms are constantly tumbling around each other and so mercury (or any other metal) cannot be magnetized as a liquid.
Not all materials are easily magnetized; those that are we call ferromagnetic materials. In ferromagnetic materials, such as an iron bar, the atoms already tend to line up with their magnetic moments pointing in the same direction, but unless an external magnetic field is applied small errors accumulate which result in the bar as a whole being non-magnetic.
If you use a strong external field, however, you can get the atoms throughout the iron bar to line up if you provide some encouragement. You can magnetize a piece of iron by stroking it with a magnet, or by placing it in a strong magnetic field and hitting it repeatedly on one end, or even by heating it red-hot and then cooling it in a strong magnetic field. However, this only works with ferromagnetic materials.
The types of magnetism are:
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