Why no J on periodic table of the elements?
926491
Luck of the draw, mostly.  Elements were named by their discoverer, and "j" is a rather rare letter, especially when one considers that elements are named with a "latin" style to them, and that there is no "j" in latin (the "j" and the "i" were the same letter for ages)
1157452
The first 92 elements of the periodic table occur naturally (from hydrogen to uranium).\n\nBTW, in reference to earlier poster, some of the naturally occurring elements (radon, radium, uranium, others) are radioactive, as well.
123587
Periodic Table is in order of increasing atomic no. so\n\n1st Step: find the placement of the element, in the present case it is on third place so no. of protons is three.\n\n2nd Step: In the Periodic Table, number of electron is always equal to number of protons so far three protons of Lithium there will be three electrons.\n\n3rd Step: Periodic Table also give atomic weights of the elements. Simply atomic weight is equal to sum of number of protons and nutroms.\n\n4th Step: Note the atomic weight of the element. Most of the elements in Periodic Table show atomic weights in fractions. In the case of Lithium it is 6.9 \n\n5th Step: Convert the fractional figure into nearest whole number. In case of Lithium it is 7\nNote:In the Periodic Table atomic weight is average of all isotopes (different atomic weights of same element). The nearest whole number refers to the most abundent  or the common atom (Isotop).\n\n6th Step: Subtract atomic number (protons) from atomic weight (neutron=proton), the difference is number of neutrons. In Lithium 7-3=4 so there are 4 neutrons
451270
its how the electrons fit into the shells around the nucleus. at gcse there are 4 and they have the rule 2.8.8.18 so the first shell is filled first with two and then the second with 8 and so on.the number of electrons in the outer most shell used gives the atom its properties and its position on the periodic table
73838
Its' probably a rounding error. It would depend on which masses for the elements you use, how precise you want to be.
12361
i sorta answered that in your other one asking the config for niobium.  There are some exceptions to the electron configuration filling rules, and that is one of them, the element is more stable because the shells are already far out basically, the electron likes having an orbital all to itself. (each orbital can contain up to 2 electrons, the s only has one orbital, and the d has 5)
1113655
Investigate the origins of the periodic table.
738963
As in sodium and potassium - Group I and magnesium and calcium - Group II?\nIf you look at the arrangement of the electrons that an atom of the above elements has:\nNa: 11, arranged as 2,8,1\nK: 19, arranged as 2,8,8,1\nBoth Na and K have 1 electron in their most outer shell. Hence they are in the 1st column, or Group I.\nMg: 12, arranged as 2,8,2\nCa: 20, arranged as 2,8,8,2\nBoth Mg and Ca have 2 electrons in their most outer shell. Hence they are in the 2nd column, or Group II.\n\nHope this helps :)
811321
http://www.chemicool.com/definition/element.html\nis this what you mean? \n\nI don't think that this is a physical property although for the life of me I can't see why it couldn't be.
791559
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.
694929
The alkali metals, also known as Group 1.  They are lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr).  The single valence electron is so easily given away that the elements lower down in the group react explosively with water.  Because they are so highly reactive, they are not found in elemental form in nature, only as ionic compunds.  They are stored under mineral oil to prevent reactions with the moisture in air.\n\nHydrogen is also in Group 1, but its single electron is held very close to the nucleus (a single proton), which means that the electron is not easily given away.  Hydrogen can form a positive or negative ion, because it can also easily accept a second electron to fill its valence shell.  Thus, it is not an alkali metal and is not a member of the family you are asking about.  However, under extremely high pressure, as occurs near the core of Jupiter, hydrogen does take on a metallic structure and behaves as an alkali metal.
360137
the simplistic answer involves the electrons, protons and neutrons. the more complex answer contains up quarks, down quarks- which are the building blocks of protons and neutrons. \nThen if we think about it we have also got anti-matter, which is involved in bonding and so forth, and so must be around somewhere. positrons, anti-bonding orbitals, etc.
689544
Na+ is missing an *electron*
831195
lose\n\nLook at your periodic table.  Ithose on the left two columns lose.  Those in the last two prior to the noble gases gain.  The others can do either but generally speaking if they have less than 4 valence electrons they lose and if the have more than 4 they gain.  If they have four such as Carbon and silicon, they can do either.  This makes for some very neat chemistry for those elements.
403502
Here is one : http://en.wikipedia.org/wiki/Periodic_table
2092
that's a trick question.. you can't have a lewis dot structure for iron.. The Lewis dot structures represent elements who's outer shell consists of electrons in the s and p orbitals, iron is in the d-block.  What i mean is that only the first two groups and the last 6 groups on the periodic table can have lewis structures, elements in the first group have one dot, second have 2, then it skips over the transition metals(which is what iron is) the 13th have 3, 14th have 4, etc up to 8.  d-orbital electrons(which are where the outer electrons of those transition metals are) are not as reactive and don't behave in the same way and so cannot have lewis structures.\n\nthat's a trick question.. you can't have a lewis dot structure for iron.. The Lewis dot structures represent elements who's outer shell consists of electrons in the s and p orbitals, iron is in the d-block.  What i mean is that only the first two groups and the last 6 groups on the periodic table can have lewis structures, elements in the first group have one dot, second have 2, then it skips over the transition metals(which is what iron is) the 13th have 3, 14th have 4, etc up to 8.  d-orbital electrons(which are where the outer electrons of those transition metals are) are not as reactive and don't behave in the same way and so cannot have lewis structures.  \n\nIf you meant electron configuration, then the electron configuration for iron is:  1s2 2s2 2p6 3s2 3p6 4s2 3d6 (where every third number is a superscript and the whole thing is written as one line) if that makes no sense, then that's not what you meant and ignore it haha...
669191
There would be no liquid nonmetallic element!!