what's the meaning  of each SPDFG? in electron orbitals?
917590
The notation 's', 'p', 'd', and 'f' originate from a now-discredited system of categorizing spectral lines.\n\ns= sharp\np= principal\nd= diffuse\nf= fundamental
436857
Good question. \n\nIt's just notation. Just like why do we show potential energy by U? Why do we show density by "rho"?
115249
Try this URL... it shows some diagrams.  Although it does not have the full set of configurations for d and f orbitals.
801097
Work through them one-by-one. You need p or d orbitals that are oriented properly. The s orbital is symmetric, so it won't work for a pi bond. \nA. s orbital is the wrong symmetry for a pi-bond.\nB. py and dxy do appear to be oriented properly\nC, D, E - all have as one choice the px. Since the bond is along this axis, the px is not oriented properly for a pi bond. (The pi-bond has to have lobes that stick out to the side perpendicular to the axis of the bond).
5016
O\n                       ^\n                       |\n                      xx\n                  H-O-Br:->O\n                      xx\n                       |\n                       V\n                       O\n\nPlace the xx above and below Br. Br donates electron pairs to three oxygen atoms. There is also one Br-O-H bond in the molecule.
784377
This is true.  The Px, Py, and Pz orbitals are degenerate in all atoms provided the atom is not subjected to a magnetic field. \n\nIn hydrogen and other single electron systems (He+ etc) only the n quantum number matters to determine energy.  So you can actually say that the 2s, 2px, 2py and 2pz are all degenerate.  \n\nThe s, p etc orbitals lose this degeneracy when there is more than one electron due to electrostatic repulsion between the electrons, so then you need both the n quantum number and the l quantum number to determine energy.
715376
It means that electrons have both particle-like and wave-like behaviour (for example they demonstrate interference).\n\nwavelength = planck's constant/(mass x velocity)
850007
The electron configuration of Sc3+ is [Ne] 3s2 3p6\nThe value of "n" is the energy level, which is 3 here.\nThe value of "l" is the orbital type. For a "p" orbital, l = 1. \nSo, the statement is true.\n\nChromium has an unusual electron configuration.\nIt is actually 1s2 2s2 2p6 3s2 3p6 4s1 3d5.\nIt seems that the atom is more stable when it has all of the orbitals in a group filled the same way, ie. half-full.\n\nGround state means that the electrons are in the lowest energy levels available. In an excited state, energy has been added to the atom, and the electrons are (temporarily) at higher levels. Which ones depends on how much energy you put into the atom.  Too much, and you remove the electron entirely.\nSo, it's not really predictable without the energy values.
1911
Noble gas configuration is with the outer electron orbital filled. This usually means having 8 electrons in the outer orbital, hence it is called the octet rule that stable compounds are in noble gas configuration. It is called this, because the configuration is the same as that of the noble gases (the elements at the far right of the periodic table).
1111040
According to quantum mechanics, electrons can be represented by wavefunctions, from which the electron density can be determined. Each electron has its own wavefunction, which is called an orbital. The exact momentum and position of an electron cannot be simultaneously determined. This is a limitation described by the Heisenberg uncertainty principle, which, in this instance, simply states that the more accurately we know a particle's position, the less accurately we can know its momentum, and vice versa.  So, exact postion of an electron impossible to determine.  Thus electron can be two places at ones.
1186592
In the quantum mechanical model of the hydrogen atom, the location of the electron is expressed in terms of a probability distribution, so one speaks of the probability that an electron will be found at a particular location near a nucleus. The probability distribution, in turn, is determined by a mathematical function known as a wavefunction, denoted y. Wavefunctions for the distribution of particles are a general feature of quantum mechanics, and for electrons in atoms they are known as atomic orbitals. The name orbital is intended to express a distribution that is less precise than the explicit orbits of the Bohr model. The probability of finding an electron at a specified location is proportional to the square of the amplitude of the wavefunction at that point. Hence, the sign (positive or negative) of the orbital is not relevant to the location of the electron, because taking the square of y eliminates any negative sign it may have.
727510
it does not have to end with the s, and in the case of calcium, which has 20 electrons, the ground state would have the configuration ending in 3d2, because it is the lower energy state, see the link it is pretty cool\n\nhttp://www.webelements.com/webelements/elements/text/Ca/econ.html
746884
if we use carbon as the example-there are four electron in the outer shell.  these would normally consist of one s shell electron and 3 p shell electrons.  instead of doing that, the 4 electrons become hybrids in that they all act the same and take on some s shell and some p shell character, so instead of having 1 and 3 of s and p type, you end up with 4 electrons of sp shell.\n\nif you kept the 1-s and 3-p configuration, the s would act one way and the p's would act another.  since they all become sp electrons, they act the same way, so in the case of something like methane (CH4), each of the hydrogens are equally spaced away from each other, kind of looking like a pyramid (they each are 109.5 degrees away from each other)
734854
I'm going to cheat a little bit in both cases by just referring back to the nearest noble gas.  That itself may be acceptable for your purposes (it's how most chemists list them because things past that point are usually of no interest)... if you need, I'll pass on the underlying noble gas configuations too.\n\n13:  [Ne] 3s2 3p1\n33:  [Ar] 4s2 3d10 4p3\n\nBasically, the electrons usually fill up the shells just as you see the elements arranged on the periodic table.  Group 1 and 2 (the two columns on the left) are the s shell, and the number of the s shell is indicated by the row number.  Group 13 through 18 (the six columns on the right) are the p shell; its number is also the same as the row number.  The middle stretch are d orbitals, and they're so expensive energetically that the ones on each row are orbitals from one shell down.  That chart is handy for all kinds of things!\n\nHope that helps!
570306
1.ATOMIC NUMBER\n2.ELECTRON\n3.SHELL\n4.ORBIT
332147
Those ions do follow Hund's rule, though. The d orbital looks like this:\n\n\n_________ ___________\n\n__**_______ ____*____ ___*____\n\nThe electrons are only paired when absolutely necessary.
817827
energy levels/orbitals