The noble gases are a group of elements which are gaseous at room temperature and pressure, and called "noble" because they rarely bond with other elements. This results from the fact that their electronic configurations consist of completely filled sublevels. The noble gasses and their atomic numbers are given in the following table.
<P> <DIV ALIGN="CENTER"> <TABLE CELLPADDING=3 BORDER="1"> <TR><TD ALIGN="LEFT">element</TD> <TD ALIGN="LEFT">symbol</TD> <TD ALIGN="RIGHT"><a href="http://scienceworld.wolfram.com/physics/AtomicNumber.html" >atomic number</a> <img src="http://scienceworld.wolfram.com/images/crossrefs/physics.gif" width="12" height="12"></TD> </TR> <TR><TD ALIGN="LEFT">Helium</TD> <TD ALIGN="LEFT">He</TD> <TD ALIGN="RIGHT">2</TD> </TR> <TR><TD ALIGN="LEFT">Neon</TD> <TD ALIGN="LEFT">Ne</TD> <TD ALIGN="RIGHT">10</TD> </TR> <TR><TD ALIGN="LEFT">Argon</TD> <TD ALIGN="LEFT">Ar</TD> <TD ALIGN="RIGHT">18</TD> </TR> <TR><TD ALIGN="LEFT">Krypton</TD> <TD ALIGN="LEFT">Kr</TD> <TD ALIGN="RIGHT">36</TD> </TR> <TR><TD ALIGN="LEFT">Xenon</TD> <TD ALIGN="LEFT">Xe</TD> <TD ALIGN="RIGHT">54</TD> </TR> <TR><TD ALIGN="LEFT">Radon</TD> <TD ALIGN="LEFT">Rn</TD> <TD ALIGN="RIGHT">86</TD> </TR> </TABLE> </DIV>
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