CHEMystery: The Periodic Table of the Elements

<BODY BGCOLOR=#000000 TEXT=#FFFFFF LINK=#FF7F00 VLINK=#00CFCF ALINK=#FFFF00> <B><SMALL> <A HREF=".." TARGET="_parent">Return</A> to the Main CHEMystery Page.<BR> <A HREF="../pertable" TARGET="_parent">Return</A> to the Periodic Table of the Elements<BR> </SMALL></B> <H1><FONT FACE="Arial"><I>Element 24 - Chromium (Cr) <A HREF="24.wav"><IMG SRC="sound.gif" ALT="sound" BORDER=0 ALIGN=top></A></I></FONT></H1> From <I>chroma</I>, or color; discovered 1797. A very bright, silvery metal, it forms compounds valued as pigments for their vivid green, yellow, red, and orange colors. The ruby takes its color from chromium. Besides lustrous chrome plate, its alloys include a number of special hard steels. <HR> <CENTER><TABLE BORDER=1 CELLPADDING=2 CELLSPACING=2> <TR><TD COLSPAN=2><CENTER><H3><FONT FACE="Arial">Properties</FONT></H3></CENTER></TD></TR> <TR> <TD><A HREF="../reference/glossary.html#atomicnumber" TARGET="_parent">Atomic Number</A>:</TD> <TD>24<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#atomicweight" TARGET="_parent">Atomic Weight</A>:</TD> <TD>51.996<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#electronconfiguration" TARGET="_parent">Electron Configuration</A> (at ground state):</TD> <TD>1s<SUP>2</SUP>2s<SUP>2</SUP>2p<SUP>6</SUP>3s<SUP>2</SUP>3p<SUP>6</SUP>3d<SUP>5</SUP>4s<SUP>1</SUP><BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#oxidationstate" TARGET="_parent">Oxidation States</A> (Bold most stable):</TD> <TD>+2, <B>+3</B>, +6<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#boilingpoint" TARGET="_parent">Boiling Point</A> (K):</TD> <TD>2945<BR></TD> </TR> <TR> <TD>Melting Point (K):</TD> <TD>2130<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#density" TARGET="_parent">Density</A> (at 300K -- g/cm<SUP>3</SUP>):</TD> <TD>7.19<BR></TD> </TR> <TR> <TD>Atomic Volume (at 300K -- cm<SUP>3</SUP>/mol) <TD>7.23<BR></TD> </TR> <TR> <TD>Number of stable <A HREF="../reference/glossary.html#isotopes" TARGET="_parent">isotopes</A>:</TD> <TD>4<BR></TD> </TR> <TR> <TD> <A HREF="../reference/glossary.html#massnumber" TARGET="_parent">Mass Number</A> (Bold naturally occurring) -- <A HREF="../reference/glossary.html#halflife" TARGET="_parent">Half-Life</A> -- <A HREF="../reference/glossary.html#radioactivedisintegrationseries" TARGET="_parent">Disintigration Type</A>: </TD> <TD> 51 -- 27.70 days -- orbital <A HREF="../reference/glossary.html#electroncapture" TARGET="_parent">electron capture</A><BR> </TD> </TR> <TR> <TD>Covalent Radius (Å):</TD> <TD>1.18<BR></TD> </TR> <TR> <TD>Atomic Radius (Å):</TD> <TD>1.30<BR></TD> </TR> <TR> <TD>First <A HREF="../reference/glossary.html#ionizationenergy" TARGET="_parent">Ionization Potential</A> (V):</TD> <TD>6.766<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#electronegativity" TARGET="_parent">Electronegativity</A> (Pauling's):</TD> <TD>1.66<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#specificheat" TARGET="_parent">Specific Heat</A> Capacity (at 300K -- J g<SUP>-1</SUP> K<SUP>-1</SUP>):</TD> <TD>0.449<BR></TD> </TR> <TR> <TD>Heat of Vaporization (kJ/mol):</TD> <TD>339.5<BR></TD> </TR> <TR> <TD>Heat of Fusion (kJ/mol):</TD> <TD>20<BR></TD> </TR> <TR> <TD>Electrical Conductivity (at 293K for polycrystalline material -- 10<SUP>6</SUP> <IMG SRC="../misc/oomega.gif" ALT="(ohms)"><SUP>-1</SUP> cm<SUP>-1</SUP>):</TD> <TD>7.9<BR></TD> </TR> <TR> <TD>Thermal Conductivity (at 300K -- W m<SUP>-1</SUP> K<SUP>-1</SUP>):</TD> <TD>93.7<BR></TD> </TR> <TR> <TD>Crystal Structure:</TD> <TD><IMG SRC="cubic-body.gif" ALIGN=middle> Cubic, body centered<BR></TD> </TR> <TR> <TD><A HREF="../reference/glossary.html#acid" TARGET="_parent">Acid</A>-<A HREF="../reference/glossary.html#base" TARGET="_parent">Base</A> Properties:</TD> <TD><IMG SRC="very-acidic.gif" ALIGN=middle> Very acidic<BR></TD> </TR> </TABLE></CENTER> <HR> <CENTER> <A HREF="ptbl_bar.map"><IMG SRC="ptbl_bar.gif" ALT="The Periodic Table of the Elements" BORDER=0 WIDTH=579 HEIGHT=49 ISMAP></A> </CENTER> </BODY>