<?xml version="1.0"?>

<!DOCTYPE periodic_table [
  <!ELEMENT periodic_table (atom*)>
  <!ELEMENT atom EMPTY>

  <!ATTLIST atom
    name   CDATA   #REQUIRED
    symbol CDATA   #REQUIRED
    number NMTOKEN #REQUIRED
    weight NMTOKEN #REQUIRED
  >
]>


<periodic_table>
  <atom name="actinium" number="89" symbol="Ac" weight="227"/>
  <atom name="aluminum" number="13" symbol="Al" weight="26.9"/>
  <atom name="americium" number="95" symbol="Am" weight="243"/>
  <atom name="antimony" number="51" symbol="Sb" weight="121.7"/>
  <atom name="argon" number="18" symbol="Ar" weight="39.9"/>
  <atom name="arsenic" number="33" symbol="As" weight="74.9"/>
  <atom name="astatine" number="85" symbol="At" weight="210"/>
  <atom name="gold" number="79" symbol="Au" weight="196.9"/>
  <atom name="boron" number="5" symbol="B" weight="10.8"/>
  <atom name="barium" number="56" symbol="Ba" weight="137.3"/>
  <atom name="beryllium" number="4" symbol="Be" weight="9.0"/>
  <atom name="bismuth" number="83" symbol="Bi" weight="208.9"/>
  <atom name="berkelium" number="97" symbol="Bk" weight="247"/>
  <atom name="bromine" number="35" symbol="Br" weight="79.9"/>
  <atom name="carbon" number="6" symbol="C" weight="12.0"/>
  <atom name="calcium" number="20" symbol="Ca" weight="40.0"/>
  <atom name="cadmium" number="48" symbol="Cd" weight="112.4"/>
  <atom name="cerium" number="58" symbol="Ce" weight="140.1"/>
  <atom name="californium" number="98" symbol="Cf" weight="251"/>
  <atom name="chlorine" number="17" symbol="Cl" weight="35.4"/>
  <atom name="curium" number="96" symbol="Cm" weight="247"/>
  <atom name="cobalt" number="27" symbol="Co" weight="58.9"/>
  <atom name="chromium" number="24" symbol="Cr" weight="51.9"/>
  <atom name="cesium" number="55" symbol="Cs" weight="132.9"/>
  <atom name="copper" number="29" symbol="Cu" weight="63.5"/>
  <atom name="dysprosium" number="66" symbol="Dy" weight="162.5"/>
  <atom name="erbium" number="68" symbol="Er" weight="167.2"/>
  <atom name="einsteinium" number="99" symbol="Es" weight="252"/>
  <atom name="europium" number="63" symbol="Eu" weight="151.9"/>
  <atom name="fluorine" number="9" symbol="F" weight="18.9"/>
  <atom name="iron" number="26" symbol="Fe" weight="55.8"/>
  <atom name="francium" number="87" symbol="Fr" weight="223"/>
  <atom name="gallium" number="31" symbol="Ga" weight="69.7"/>
  <atom name="gadolinium" number="64" symbol="Gd" weight="157.2"/>
  <atom name="germanium" number="32" symbol="Ge" weight="72.6"/>
  <atom name="hydrogen" number="1" symbol="H" weight="1.0"/>
  <atom name="helium" number="2" symbol="He" weight="4.0"/>
  <atom name="hafnium" number="72" symbol="Hf" weight="178.4"/>
  <atom name="mercury" number="80" symbol="Hg" weight="200.5"/>
  <atom name="holmium" number="67" symbol="Ho" weight="164.9"/>
  <atom name="iodine" number="53" symbol="I" weight="126.9"/>
  <atom name="indium" number="49" symbol="In" weight="114.8"/>
  <atom name="iridium" number="77" symbol="Ir" weight="192.2"/>
  <atom name="potassium" number="19" symbol="K" weight="39.0"/>
  <atom name="krypton" number="36" symbol="Kr" weight="83.8"/>
  <atom name="lanthanum" number="57" symbol="La" weight="138.9"/>
  <atom name="lithium" number="3" symbol="Li" weight="6.9"/>
  <atom name="lutetium" number="71" symbol="Lu" weight="174.9"/>
  <atom name="magnesium" number="12" symbol="Mg" weight="24.3"/>
  <atom name="manganese" number="25" symbol="Mn" weight="54.9"/>
  <atom name="molybdenum" number="42" symbol="Mo" weight="95.9"/>
  <atom name="nitrogen" number="7" symbol="N" weight="14.0"/>
  <atom name="sodium" number="11" symbol="Na" weight="22.9"/>
  <atom name="niobium" number="41" symbol="Nb" weight="92.9"/>
  <atom name="neodymium" number="60" symbol="Nd" weight="144.2"/>
  <atom name="neon" number="10" symbol="Ne" weight="20.1"/>
  <atom name="nickel" number="28" symbol="Ni" weight="58.6"/>
  <atom name="neptunium" number="93" symbol="Np" weight="237.0"/>
  <atom name="oxygen" number="8" symbol="O" weight="15.9"/>
  <atom name="osmium" number="76" symbol="Os" weight="190.2"/>
  <atom name="phosphorus" number="15" symbol="P" weight="30.9"/>
  <atom name="protactinium" number="91" symbol="Pa" weight="231.0"/>
  <atom name="lead" number="82" symbol="Pb" weight="207.2"/>
  <atom name="palladium" number="46" symbol="Pd" weight="106.4"/>
  <atom name="promethium" number="61" symbol="Pm" weight="145"/>
  <atom name="polonium" number="84" symbol="Po" weight="209"/>
  <atom name="praseodymium" number="59" symbol="Pr" weight="140.9"/>
  <atom name="platinum" number="78" symbol="Pt" weight="195.0"/>
  <atom name="plutonium" number="94" symbol="Pu" weight="244"/>
  <atom name="radium" number="88" symbol="Ra" weight="226.0"/>
  <atom name="rubidium" number="37" symbol="Rb" weight="85.4"/>
  <atom name="rhenium" number="75" symbol="Re" weight="186.2"/>
  <atom name="rhodium" number="45" symbol="Rh" weight="102.9"/>
  <atom name="radon" number="86" symbol="Rn" weight="222"/>
  <atom name="ruthenium" number="44" symbol="Ru" weight="101.0"/>
  <atom name="sulfur" number="16" symbol="S" weight="32.0"/>
  <atom name="silver" number="47" symbol="Ag" weight="107.8"/>
  <atom name="scandium" number="21" symbol="Sc" weight="44.9"/>
  <atom name="selenium" number="34" symbol="Se" weight="78.9"/>
  <atom name="silicon" number="14" symbol="Si" weight="28.0"/>
  <atom name="samarium" number="62" symbol="Sm" weight="150.3"/>
  <atom name="strontium" number="38" symbol="Sr" weight="87.6"/>
  <atom name="tantalum" number="73" symbol="Ta" weight="180.9"/>
  <atom name="terbium" number="65" symbol="Tb" weight="158.9"/>
  <atom name="technetium" number="43" symbol="Tc" weight="98"/>
  <atom name="tellurium" number="52" symbol="Te" weight="127.6"/>
  <atom name="thorium" number="90" symbol="Th" weight="232.0"/>
  <atom name="tin" number="50" symbol="Sn" weight="118.7"/>
  <atom name="titanium" number="22" symbol="Ti" weight="47.8"/>
  <atom name="thallium" number="81" symbol="Tl" weight="204.3"/>
  <atom name="thulium" number="69" symbol="Tm" weight="168.9"/>
  <atom name="uranium" number="92" symbol="U" weight="238.0"/>
  <atom name="vanadium" number="23" symbol="V" weight="50.9"/>
  <atom name="tungsten" number="74" symbol="W" weight="183.8"/>
  <atom name="xenon" number="54" symbol="Xe" weight="131.2"/>
  <atom name="yttrium" number="39" symbol="Y" weight="88.9"/>
  <atom name="ytterbium" number="70" symbol="Yb" weight="173.0"/>
  <atom name="zinc" number="30" symbol="Zn" weight="65.3"/>
  <atom name="zirconium" number="40" symbol="Zr" weight="91.2"/>
</periodic_table>



