describe the three rules that govern the filling of orbitals by electrons.?
927180
Here are the rules as far as I know...\n\n1. The maximum capacity of each shell is given by 2n^2 (where n is the shell number starting from the innermost shell)\n2. The maximum capacity of the last shell, regardless of the atom, is 8.\n3. The maximum capacity of the penultimate shell (the second last shell) is not more than 18.
814740
Look at the proton number, which is 23. That means the electron arrangement ends in 3d3 4s2.  Hund's Rule suggests that the 3d3 electrons go in separate orbitals before being forced to pair up, so a V atom has 3 unpaired electrons.
29638
The internal structure of an atom (in terms of its protons and neutrons) will create regions which are called orbitals.  We commonly think of atoms according to the Bohr model, where electrons orbit the nucleus like little planets.  This model is wrong.  the truth is that we can only determine the location of an electron based on a statistical model, and that gives us regions where electrons are more likely or less likely to be found if we searched for them there.  These areas where electrons are most likely to be found are called orbitals.\n\nThe orbitals differ in energy states.  An electron in a high orbital needs high energy, and electrons with less energy will be at lower orbitals.  When the number of electrons and protons are equal (ie the atom is not an ion) and the electrons occupy all of the lowest energy orbitals possible, that is called the ground state.\n\nif an electron at the ground state gets extra energy, it can jump to a higher orbital.  However, the various orbitals require certain, specific amounts of energy, and the energy gaps between the orbitals are specific amounts of energy, based on the orbital structure dictated by the nucleus (the details of all of this require some of the ugliest differential equations and eigenfunctions you're likely to ever see).  So the energy absorbed by an electron to jump from a low orbital to a high orbital must be of a specific amount.  After time, the electron will eventually relax back to the lower orbital.  When it does, it will release its excess energy in the form of a photon with the precise amount of energy that spearates the two orbitals.\n\nFor a given atom, there is a certain number of specific orbital transitions possible, and each possible transition will correspnd to a single band on the spectrum produced by the pure element when heated to.  So while a given atom can give several colors, the number of colors it can give are limited.
873575
Reactivity...Nitrogen requires 3 electron to fill its outer shell and oxygen only two.  10 points please.
722082
s,p,d and f are designations for the four different types of orbitals.\n\ns is spherical in shape and has only one orientation in three dimensional space.\n\np has a dumbbell shape and has three orientations in 3-d space:\nPx,Py and Pz.\n\nd has a double dumbbell shape and has 5 orientations in 3-d space.\n\nf has a complex shape and has 7 orientations.\n\nEach orbital can hold 2 electrons. s having only 1 orientation can hold only 2 electrons. p having 3 orientations, has 3 orbitals, each having the capacity to hold 2 electrons, so it can totally hold (3*2=) 6 electrons.\nSimilarly d can hold (5*2=) 10 electrons and f can hold (7*2=) 14 electrons.
827235
100% sure\n1. D\n2. B\n3. D (electrons become part of the WATER molecule which eventually reacts with hydrogen to form water)
937236
The electrons of an atom are arranged in shells. These shells can be completely filled or only partly. The  elements in the same period have the same number of completely filled or closed shells.
946929
all the electrons are located in the electronic orbitals of the ion.\n\nYou may find this useful:\n\nhttp://www.owlnet.rice.edu/~chem251/documents/Vollhardt_1.ppt
660043
1.) do your own homework\n2.) this is the computer forum, not high-school chemistry.  Next time post to the right furom.
613790
Maybe this wil lhelp.         \n\n ELECTRON DOT DIAGRAMS\n1. Let the element's SYMBOL represent the nucleus and inner energy level .\n2. Write the ELECTRON CONFIGURATION for the element (or look at the PERIODIC table).  Count the electrons in the OUTER energy level.\n3. Let the top, bottom, and two sides represent the ORBITALS.\nPlace the appropriate number of DOTS in each "orbital".\nUse ONE dot if the orbital has 1 electron and TWO dots if the orbital has 2 electrons.  The electron dot diagrams for:\n \nNa(Z=11)  1s2   2s2   2p6  3s1       Na\n \nMg(Z=12)  1s2   2s2   2p6  3s2             Mg\n \nAs(Z=33)  1s2   2s2   2p6  3s2  3p6  4s2  3d10  4p3      As\n \nThe periodic table can also be used to write electron dot diagrams.\nAll the elements in the first column have ONE outer electron(s).  They have ONE dot(s) in their electron dot diagram. All of the elements in column 2 have TWO outer electrons.  They have TWO dots in their electron dot diagram.  Most of the elements in column 18 have EIGHT outer electrons except HELIUM which only has TWO outer electrons.  All of the elements in column 18 have EIGHT dots in their electron dot diagram except HELIUM  which only has TWO.
347007
The valency is determined by how many electrons the atom is using to bond with another atom to form a compound. The electrons in the outermost orbit generally forms the bonds. For materials having multiple electrons in the outermost orbit the element can have different valencies. Whatever happens tends to lower the the total energy of the system to make it stable.
17774
It doesn't give me room to list them all and explain them on here so let me direct you to a website I found that does a pretty good job:\nhttp://vergil.chemistry.gatech.edu/notes/quantrev/node20.html
589079
For this you should see the electronic configuration of those elements.\nThe metals with atomic number 21-30 are transition metals; they have outer 4s shell complete and the inner 3d orbital is 'in the process' of being filled up. They all have 2 outermost electrons in the 4s2 shell. \nIonization energy is the energy required in removing an outer most electron from a neutral atom. The transition metals and calcium have their outermost 2 electrons in 4s which means that their electrons experience the same force of attraction from the nucleus (being at the same distance from the nucleus) ; hence almost the same amount of energy will be required to overcome that attractive force to remove the electrons.
291938
1. electron\n2. ionic\n3. molecules of compounds\n4. decomposition (not sure)
787571
When the charges are different, you give the electron configuration for the element that has that number of electrons. For example, Na+ is like Na, but it is missing an electron, so the configuration is simply [Ne]\n\nfor O2-, it has gained 2 electrons, so it is also [Ne]\n\nCo2+ has lost 2 electrons so it is [Ar] 4s2 3d5
103358
initially,the 4th orbit occupies 8 e-'s, & next orbit is filled but at times when higher levelorbit(5)get's filled (4th)it takes up 18(total)e-'s\nfurther refer text...for quantum mechanics filling is done in reff.to AUFBAU RULE.
493325
It is because a a shell can occupy only a maximum of 8 electrons which satisfies the octet rule.\n\n the rules are:\nHUND's rule of maximum multiplicity\nPAULI's exclusion principle\nAUFBAU principle