alos how many electrons can be accommodated in outer shell of oxygen?
216534
There are 8 electrons in an oxygen atom.  The first shell can hold up to 2, so this leaves 6 for the second shell.  The second shell can hold up to 8, which is what happens when oxygen becomes an oxide ion.  It gains two electrons and obtains a -2 charge, and has an electron configuration identical to that of neon.
447055
Se has the electron arrangement 4p4. One of the 4p orbitals will be full holding 2 electrons.\nTwo of the 4p orbitals will have one electron each in - ie half full
503812
You apparently know what the diagonal rule looks like, but the link below gives a quite nice picture of it.\n\nBasically it is a summary of the order in which electron shells will be filled up. Follow the arrows round to discover where the electrons will go, starting at the 1s level.\n\nSo for 15:\n2 electrons will go into 1s, filling that up\n1s2\nthe next electrons will go into 2s2, 2p6, 3s2 and then the remaining 3 electrons into the 3p orbital, giving us a structure of:\n1s2 2s2 2p6 3s2 3p3\nRemeber, on your diagram, the first two characters (2p, 4d etc) are the names of the orbital, and the final digit is the number of electrons in that orbital. On your diagram the final digit shows the maximum number of electrons on the orbital; when you write out the structure the first few orbitals will be full (1s2 2s2 2p6 3s2) and the last one will be part full of however many electrons you have left (3p3.)
346929
They are all row three transitions metals.  So the point about 5 valence electrons is correct depending on the oxidation state of the atom.
425109
well since o2- has an extra 2 electrons it gives it 10 electrons total making it the same electron configuration as neon which is a noble gas....so the elec. config for o2- is [Ne]
481051
B.the electron subshell
410175
Let's see, this may be a bit difficult to explain, but since no one else has so far, I figured I'd give it a shot.\n\nI don't have a periodic table in front of me, so I'll do my best to explain.  There is a double bond between N and one of the O's because of something called "in-bonds."  You determine the number of "in-bonds," or bonds in between elements by subtracting the number of valence electrons that you have all together from the number that you need for everything to be stable.  In this case, forget about H for the time being, and you have N03.  Each element needs 8 electrons to fill its valence shell right?  Multiply 8 by 4, since there are 4 elements, and you get 32.  However, you only have 24 electrons to go 'round.  The difference is 8, there for you can have a total of 8 electrons, or 4 individual bonds in between the elements.  It doesn't matter which O gets to share the double bond with N, as they are all the same.\n\nThe double bond was used in HNO3 and not NF3 because I believe you had enough electrons to go around, therefore there were no "in-bonds."\n\nI hope this helps to clear up your questions.
484472
None of the first two row elements can exceed 8 valance electrons.\n\nCarbon can make four covalent bonds. Oxygen (typically) only makes two covalent bonds since it already has two lone pairs. And hydrogen can only ever have one bond.
423632
Nitrogen might be what you are looking for as it is a gas and is next to Oxygen in the periodic table so it has similar mass.\n\nBut as the person above has said, some kind of gaseous sulfur would have the closest properties to oxygen.
463867
empty and filled\n\nIt can be both empty or filled dependign on which shell you consider to be the outer shell. The outer shell can be the outermost shell to contain electrons, which is filled. Or it can be the next outermost shell, which is empty in an atom but could become the valence shell in an ion.
164135
it is coz of the one valance electron in the outer most shell
343693
Each n level can contain at most 2n^2 electrons\n\nSo at the fifth level, 2n^2 = 50.\n\nNote: the first four levels contain 60 electrons.\nSo we have 50 in the fifth level.\nand 5 left over for the 6th level.
188185
No it's false. It's an Ionic bond (e.g.: Na+Cl-)\n\nA Covalent bond is where two atoms opt to share electrons (to complete their valence shell) e.g.: atomic Oxygen has 6 valence shell electrons (L shell or 2s2,2p4) by sharing two of it's electrons with two from another Oxygen atom means that the four electrons shared form 2 covalent bonds and give the impression (if you will) that each oxygen has 8 valent electrons (a complete L shell)
299966
Aluminium has a valanly of 3 Oxgygen has 2\nSo\n4Al + 3O2   -> 2Al2O3
407222
yes O2- is neon \n\nMn2+ would look like V\n\nMn2+ has 2 less electrons that Mn
548756
Mn(+3) has the electronic configuration of 1s(2) 2s(2) 2p(6) 3s(2) 3o(6) 3d(2)\n\nthe one before me missed the 4s2 so his is wrong
366627
If there are only 3 electrons, then the maximum number of orbitals in that subshell is 3. however, if you meant magnetic quantum number of +3 - as in ml = -3, -2, -1, 0, +1, +2, +3, then that's the f subshell which has 7 orbitals.