Can someone explain to me the concept of paramagnetism?
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Paramagnetic materials are attracted when subjected to an applied magnetic field. The alignment of the atomic dipoles with the magnetic field tends to strengthen it and is described by a relative magnetic permeability greater than unity (or, equivalently, a small positive magnetic susceptibility).\n\nParamagnetism requires that the atoms individually have permanent dipole moments even without an applied field, which typically implies a unpaired electrons in the atomic or molecular orbitals. In pure paramagnetism, these atomic dipoles do not interact with one another and are randomly oriented in the absence of an external field, resulting in zero net moment. If they do interact, they can spontaneously align or anti-align, resulting in ferromagnetism (permanent magnets) or antiferromagnetism, respectively. Paramagnetic behaviour can also be observed in ferromagnetic materials that are above their Curie temperature, and in antiferromagnets above their Neel temperature.\n\nIn atoms with no permanent dipole moment, e.g. for filled electron shells, a weak dipole moment can be induced in a direction anti-parallel to an applied field, an effect called diamagnetism. Paramagnetic materials also exhibit diamagnetism, but the latter effect is typically orders of magnitude weaker. Paramagnetic materials in magnetic fields will act like magnets but when the field is removed, thermal motion will quickly disrupt the magnetic alignment. In general paramagnetic effects are small (magnetic susceptibility of the order of 10−3 to 10−5).
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http://www.vrml.k12.la.us/mike/Intech2/learning_about_magnets.htm\n\nCHECK IT OUT
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Hey there:\n\nInteresting question, because a month ago, i stumbled upon a thrown away harddrive while walking my dog.  I desembled it while I was at home, and found inside it TWO EXTREMELY POWERFULL RARE EARTH MAGNETS.  Also, around on each side of these magnets, was a magnetic shield, that did not allow them to attract from one side, but yes from the other.  If I was you, look for any thrown away harddrive, they all have them, and you will also be getting an extremly powerfull magnet while you are at it.
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Hi. From the web : "The quantum nuclear-spin relaxation rate (T-11) is computed as functions of magnetic field and temperature. A possibility that T-11 can be used as a magnetic probe in studying the electron-electron interaction in high-mobility 2DEG systems is discussed." I would say there was an effect.
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Magnetic property of a material is due to the arrangement of Domains in it. If you are not of science background, simply think it as it is the arrangement of atoms of the material, which is responsible for its magnetism. If you provide a permanent magnet with electric supply, the arrangement of atoms in it will be disturbed resulting in loss or decrease in its magnetism.\nNot only the electric supply, but heating or even strong jerks can also lead to the disturbed atomic arrangement and therefore decreased or completely lost magnetism.
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start here:\nhttp://en.wikipedia.org/wiki/Magnet
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Ferromagnetism and the Curie temperature were explained by Weiss in terms of a huge internal field, the ‘molecular field’ proportional to the magnetization. No such magnetic field really exists, but it is a way of representing the effect of quantum mechanics on the Coulomb interaction.  The Weiss model can be applied to localized or delocalized electrons. Heisenberg represented the interaction of two localized spins S1 and S2 by the Hamiltonian H = -2JS1.S2. When J> 0, the exchange is ferromagnetic, leading to ferromagnetic order but when J<0, the exchange is antiferromagnetic, leading to magnetic order that depends on lattice topology.\n\nIt is not possible to discuss the mathematics here, but one can find it on the internet. For example, see:
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Here, this question asks you for three things: Bond order, unpaired electron, and whether each is paramagnetic or diamagnetic. I figure that you already know what molecular orbital model is? Right? If you do, this problem is very very easy to approach. Look in your text book or google it for more info. Anways, I'll list the asnwer like this:\n--Bond Order:--Unpaired electron:--Dia-/Para:\nF2+ has  1.5;          1;                  P\nF2 has    1;           0;                  D\nF2- has   0;           1;                  P\n\nRemember the + means there is one less electron and - means there's one more. Also, I'm doing the Bond Order in my head so check again to make sure. Ask me any question regarding on this problem. It's very simple so I don't think you have much problem here.
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All normal matter is composed of particles such as protons, neutrons and electrons, and all of these have the fundamental property of quantum mechanical spin. Spin gives each one of these particles an associated magnetic field. Because of this, and the fact that the average microscopic piece of matter contains huge numbers of these particles, it would be expected that all matter would be magnetic. Even antimatter would have magnetic characteristics. However, everyday experience shows that this is not the case.\n\nWithin each atom and molecule, the spin of each of these particles is highly ordered as a result of the Pauli Exclusion Principle. However, there is no long range ordering of these spins between atoms and molecules. Without long range ordering, there is no net magnetic field because the magnetic moment of each one of the particles is cancelled by the magnetic moment of other particles.\n\nPermanent magnets are special in that long range ordering does exist. The highest degree of ordering exists within magnetic domains. These domains can be likened to microscopic neighbourhoods in which there is a strong reinforcing interaction between particles, and as a result, a great deal of order. The greater the degree of ordering within and between domains, the greater the resulting field will be.
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unpaired electrons are 2 according to mollecular orbital (2) theory. that's why oxygen is paramagnetic. but from the VSEPR theory, this charactoristics of O2 can not be recognised. \n\nI can not draw the diagram of MO theory otherwise I would have shown you how there is 2 unpaired electrons. In short, in the pie 2P orbital, there are 2 unpaired electrons. So, the answer is 2.
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NO.......magnetic monopoles havent been discovered yet.\nSo magnetism is still in accordance with Maxwell's equation,\ndiv(B)=0
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The permeability of space is given the symbol of the greek letter mu.\nThe permeability of free space (vaccuum) has a value of \n4 * pi * 10 ^(-7)     H*m^(-1)\n\nThe permeability of free space is, AND I EMPHASISE THAT THIS IS ONLY A CONCEPTUAL DESCRIPTION, how hard it is to set up a magnetic field in whatever medium we are considering.\n\nAll of magnetics depend on the permeability of free space - it is used in almost every calculation of magnetic field strength.\n\nTry searching wikipedia for "Ampere's Law"\nOr Maxwell's Correction to Ampere's Law (Displacement current)\nThe latter is the most fundamental equation for how currents and varying E fields set up magnetic fields, and, as you will see, the equation has mu in it!!\n\n:)
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A magnet is an object that has a magnetic field. The word magnet comes from the Greek (magnētēs lithos), which means "magnesian stone". Magnesia was an area in Ancient Greece, in present-day Manisa, Turkey where deposits of magnetite have been discovered since antiquity.\n\nElectronic generation of magnetism\nElectrons play the primary role in generating a magnetic field. Within an atom, electrons can exist either individually or in pairs within any given orbital. When they are paired, the individuals in that pair always have opposite spin — one up, one down. The fact that the spins have opposite orientation means that the two cancel one another. If all electrons are paired, no net magnetic field will be generated.\n\nIn some atoms, there are electrons that are unpaired. All magnets have unpaired electrons, but not all atoms with unpaired electrons are ferromagnetic. In order for the material to become ferromagnetic, not only must there be unpaired electrons present, but those unpaired electrons must interact with one another over long ranges such that they are all oriented in the same way. The specific electron configuration of the atoms (as well as the distance between atoms) is what leads to this long range ordering. The electrons find that they can exist in a lower energy state if they all have the same orientation.\n\n\nNorth-south pole designation and the Earth's magnetic field\nA standard naming system for the poles of magnets is important. Historically, the terms north and south reflect awareness of the relationship between magnets and the earth's magnetic field. A freely suspended magnet will eventually orient itself north-to-south, because of its attraction to the north and south magnetic poles of the earth. The end of a magnet that points toward the Earth's geographic North Pole is labeled as the north pole of the magnet; correspondingly, the end that points south is the south pole of the magnet.\n\nThe Earth's current geographic north is thus actually its magnetic south. Confounding the situation further, magnetised rocks on the ocean floor show that the Earth's magnetic field has reversed itself in the past, so this system of naming is likely to be backward at some time in the future.\n\nFortunately, by using an electromagnet and the right hand rule, the orientation of the field of a magnet can be defined without reference to the Earth's geomagnetic field.\n\nTo avoid the confusion between geographic and magnetic north and south poles, the terms positive and negative are sometimes used for the poles of a magnet. The positive pole is that which seeks geographical north.\n\n\nCommon uses for magnets\nMagnetic recording media: Common VHS tapes contain a reel of magnetic tape. The information that makes up the video and sound is encoded on the magnetic coating on the tape. This is why magnets will destroy the information in these types of tapes. Common audio cassettes also rely on magnetic tape. Similarly, in computers, floppy disks and hard disks record data on a thin magnetic coating. \nCredit, debit, and ATM cards: All of these cards have a magnetic strip on one of their sides. This strip contains the necessary information to contact an individuals financial institution and connect with their account(s). \nCommon televisions and computer monitors: The vast majority of TV's and computer screens rely in part on an electromagnet to generate an image--see the article on cathode ray tubes for more information. Plasma screens and LCDs rely on different technology entirely. \nLoudspeakers and microphones: Loudspeakers actually rely on a combination of a permanent magnet and an electromagnet. A speaker is fundamentally a device to convert electric energy (the signal) into mechanical energy (the sound). The electromagnet carries the signal, which generates a changing magnetic field that pushes and pulls on the field generated by the permanent magnet. This pushing and pulling moves t
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The Zeeman effect is the splitting of atomic spectra in the presence of a magnetic field. A certain spectral line without the field will be observed but contains more than one quantum state for the electrons there. The multiple states are indistinguishable (e.g. magnetic quantum number) until a magnetic field is applied. In the field the single spectral line splits to reveal a more complex structure.\n\nHere's more detail;\n\nhttp://en.wikipedia.org/wiki/Zeeman_effect#Strong_Field_.28Paschen-Back_effect.29
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A magnetic field is produced by moving electric charge (electric current). The strength of the field depends on the size of the current.\nBigger current -> Bigger magnetic field, i.e stronger magnet.\n\nIn "permanent magnets" the "current" is a result of atoms aligning theselves (their spins actually) in the same way, such that electrons "orbiting" the atoms (spin) result in a virtual current loop around the outside of the magnetic material. Inside the material their is no such virtual current since the current from one atom is cancelled by current in the opposite direction from a neighbouring atom, but at the outside of the material there is no neighbouring atom to balance the current. The more atoms that are in alignment the greater this virtual current and the greater the strength of the magnet. There is a theoretical maximum magnet strength for a given peice of material: that strenth when the spins of all the atoms are aligned.\n\nVisualizing a box full of spinning tops might aid understanding. Furthermore imagine what would happen if you could wrap a string around the group of tops. Imagine the string is effected by the tops motions, but the tops motions are not affected by the strings motion.
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to explain how two electrons can be near each other
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Okay, it's been a looooooong time since I had to use my chemistry skills, so lets see what I have:\n\nCopper is more magnetic with electrons than silver is because it's electrons (with fewer of them) are close to the nucleus (or whatever you call it) of the element.  Silver is more apt to lose its electrons with them being so far away.  \n\nCopper is more often found in a +2 state.  So I'd say that's a safe bet to go with.  I'd only assume a +1 state if your teacher said so.\n\nSo therefore:  2AgNO3 + Cu -> Cu(NO3)2 + 2 Ag would probably be your best bet.\n\nBut once again, it's been a long time since I used this so I don't know how right I might be.