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<!doctype html> <html lang="en"> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0">  <script async src="https://www.googletagmanager.com/gtag/js?id=G-ZK1E8XKBLT"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-ZK1E8XKBLT'); </script>  <title>WebElements Periodic Table » Protactinium » the essentials</title> <meta name="Description" content="This WebElements periodic table page contains the essentials for the element protactinium"> <meta name="keywords" content="protactinium, <?php print protactinium ?> atomic weight, periodicity, periodic table, chemical elements, <?php print protactinium ?> CAS registry, <?php print protactinium ?> atomic number, element name, element symbol, <?php print protactinium ?> atomic weight, standard state, colour, color, period,<?php print protactinium ?> description, isolation, chemistry, periodic table, 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alt="WebElements logo"></a> <a class="white" href="./">Protactinium - <sub>91</sub>Pa</a>  <audio id="myAudio_f"> <source src="../_media/elements/snds_f/Pa.mp3" type="audio/mpeg">Your user agent does not support the HTML5 Audio element. </audio> <button class="pure-button f_button" style=" display: inline;" type="button" onclick="audf_play_pause()"> 🔊  </button> <script> function audf_play_pause() { var myAudiof = document.getElementById("myAudio_f"); if (myAudiof.paused) { myAudiof.play(); } else { myAudiof.pause(); }} </script></span> </div> </div> </div> <div id="main">  <div class="pure-u-1 pure-u-sm-1-1"> <div class="pure-menu pure-menu-horizontal pure-menu-scrollable"> <a href="#" class="pure-menu-link pure-menu-heading">▸▸</a> <ul class="pure-menu-list"> <li class="pure-menu-item">🇬🇧 Protactinium</li> <li class="pure-menu-item">🇺🇦 Протактиній</li> <li class="pure-menu-item">🇨🇳 鏷</li> <li class="pure-menu-item">🇳🇱 Protactinium</li> <li class="pure-menu-item">🇫🇷 Protactinium</li> <li class="pure-menu-item">🇩🇪 Protactinium</li> <li class="pure-menu-item">🇮🇱 פרוטקטיניום</li> <li class="pure-menu-item">🇮🇹 Protoattinio</li> <li class="pure-menu-item">🇯🇵 プロトアクチニウム</li> <li class="pure-menu-item">🇵🇹 Protactínio</li> <li class="pure-menu-item">🇪🇸 Protactinio</li> <li class="pure-menu-item">🇸🇪 Protaktinium</li> <li class="pure-menu-item">🇷🇺 Протактиний</li> </ul> </div> </div> <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-1"> <div class="google_navbar_positioning"> <form action="https://www.google.com" id="cse-search-box"> <div> <input type="hidden" name="cx" value="partner-pub-9334432533380510:6223510783"> <input type="hidden" name="ie" value="UTF-8"> <input type="text" name="q" size="28"> <input type="submit" name="sa" value="Search"> </div> </form> <script> </script> </div> </div> </div> <main> <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-1"> <h1 class="f">Protactinium - <sub><small>91</small></sub>Pa: the essentials</h1> <div class="pure-menu pure-menu-horizontal pure-menu-scrollable"> <ul class="pure-menu-list z_menu"> <li class="pure-menu-item f"><a href="../protactinium/" class="pure-menu-link">▸▸ Pa Essentials</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/physics.html">Physical properties</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/atoms.html">Electron shell data</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/atom_sizes.html">Atom sizes</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/electronegativity.html">Electronegativity</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/isotopes.html" >Isotopes and NMR</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/crystal_structure.html">Crystal structure</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/thermochemistry.html">Thermochemistry</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/history.html">History</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/uses.html">Uses</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/geology.html">Geology</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/biology.html">Biology</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/compounds.html">Binary compounds</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/compound_properties.html" >Compound properties</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/chemistry.html">Element reactions</a></li> <li class="pure-menu-item f"><a class="pure-menu-link" href="../protactinium/contents.html">List all Pa properties</a></li> </ul> </div> </div> </div>  <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-2">  <ul class="ul_facts_table"> <li><a href="../periodicity/name_english/" title="Element names">Name</a>: protactinium</li> <li><a href="../periodicity/name_english/" title="Element symbol">Symbol</a>: Pa</li> <li><a href="../periodicity/atomic_number/" title="Element atomic number">Atomic number</a>: 91 </li> <li><a href="../periodicity/atomic_weight/" title="Element atomic weight">Relative atomic mass (<i>A</i><sub>r</sub>)</a>: 231.03588 (2) </li> <li><a href="../periodicity/standard_state/" title="Element standard state">Standard state</a>: solid at 298 K</li> <li><a href="../periodicity/standard_state/" title="Element colour">Appearance</a>: silvery metallic</li> <li><a href="../periodicity/classification/" title="Classification of protactinium as metal, non-metal, or semi-metal">Classification</a>: Metallic </li> </ul> </div> <div class="pure-u-1 pure-u-sm-1-2"> <ul class="ul_facts_table"> <li><a href="../periodicity/group_number/" title="The group within which protactinium is located">Group in periodic table</a>: </li> <li><a href="../periodicity/group_number/" title="The name of the group (if there is one) within which protactinium is located">Group name</a>: Actinoid</li> <li><a href="../periodicity/group_number/" title="The period within which protactinium is located">Period in periodic table</a>: 7 (actinoid)</li> <li><a href="../periodicity/group_number/" title="The block within which protactinium is located">Block in periodic table</a>: f</li> <li><a href="../periodicity/electron_shell_structure/" title="Shell structure">Shell structure</a>: 2.8.18.32.20.9.2 </li> <li><a href="../periodicity/cas_registry_id/" title="Chemical Abstract Service (CAS) Registry numbers for the elements">CAS Registry</a>: 7440-13-3</li> </ul> </div> </div> <p class="p_first"> Protactinium atoms have 91 electrons and the <strong><a href="../periodicity/electron_shell_structure/">shell structure</a></strong> is 2.8.18.32.20.9.2. The <strong> <a href="../periodicity/electronic_configuration/">ground state electronic configuration of neutral protactinium is</a></strong> [<strong>Rn</strong>].<strong>5f</strong><sup>2</sup>.<strong>6d</strong><sup>1</sup>.<strong>7s</strong><sup>2</sup> and the <strong><a href="../periodicity/term_symbol/">term symbol of protactinium </a> is</strong> <sup>4</sup><strong>K</strong><sub>11/2</sub>. </p> <h2 class="f">Protactinium: description  <audio id="myAudio_desc"> <source src="../_media/elements/snds_description/Pa.mp3" type="audio/mpeg">Your user agent does not support the HTML5 Audio element. </audio> <button class="pure-button f_button" style="display: inline;" type="button" onclick="auddesc_play_pause()">🔊</button> <script> function auddesc_play_pause() { var myAudiodesc = document.getElementById("myAudio_desc"); if (myAudiodesc.paused) { myAudiodesc.play(); } else { myAudiodesc.pause(); }} </script> </h2> <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-1"> <p class="p_first">Protactinium has a bright metallic lustre which it retains for some time in air. The element is superconductive below 1.4 K. The element is a dangerous toxic material and requires precautions similar to those used when handling plutonium. Protactinium is one of the rarest and most expensive naturally occurring elements. The element is an α-emitter and is a radiological hazard similar to polonium. Protactinium is a highly toxic and radioactive rare earth metal that requires special handling. It is found in pitchblende and ores form Zaire and is one of the rarest and most expensive naturally occurring elements.</p> <p class="pure-img"><img src="../_media/elements/element_pictures/Pa.jpg" alt="protactinium" /><br />This sample of uraninite contains some about 10<sup>-6</sup> grammes of actinium at any one time. Image adapted with permission from <a href="https://chemistry.unt.edu/people-node/james-l-marshall">Prof James Marshall</a>'s (U. North Texas, USA) <em>Walking Tour of the elements</em> CD.</p> </div> </div>  <div class="pure-g display_table"> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: physical properties</h2> <ul class="spark_table_list"> <li><a href="../periodicity/density/" title="view definition and images showing periodicity for density of elemental solids"><img alt="Density of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Density of solid</a>: 15370 kg m<sup>-3</sup></li> <li><a href="../periodicity/molar_volume/" title="view definition and images showing periodicity for molar volumes of the elements"><img alt="Molar volume of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Molar volume</a>: 15.18 cm<sup>3</sup></li> <li><a href="../periodicity/thermal_conduct/" title="show definition and view pictures showing periodicity of thermal conductivity in the periodic table"><img alt="Thermal conductivity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Thermal conductivity</a>: 47 (estimate) W m<sup>‑1</sup> K<sup>‑1</sup></li> </ul> <p><a class="pure-button" href="./physics.html">More physical properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: heat properties</h2> <ul class="spark_table_list"> <li><a href="../periodicity/melting_point/" title="show definition and view pictures showing periodicity of melting point in the periodic table"><img alt="Melting point on a miniature periodic table spark table" src="data:image/png;base64,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" /> Melting point</a>: 1841 [1568 °C (2854 °F)] K</li> <li><a href="../periodicity/boiling_point/" title="show definition and view pictures showing periodicity of boiling point in the periodic table"><img alt="Boiling point on a miniature periodic table spark table" src="data:image/png;base64,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" /> Boiling point</a>: 4300 [ca. 4000 °C (7232 °F)] K</li> <li><a href="../periodicity/enthalpy_fusion/" title="show definition and view pictures showing periodicity of fusion enthalpy in the periodic table"><img alt="Enthalpy of fusion on a miniature periodic table spark table" src="data:image/png;base64,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" /> Enthalpy of fusion</a>: 20.5 kJ mol<sup>-1</sup></li> </ul> <p><a class="pure-button" href="./thermochemistry.html">More thermochemical properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: atom sizes</h2> <ul class="spark_table_list"> <li><a href="../periodicity/atom_radius_emp/" title="View atomic radius data for the elements"><img alt="Atomic radius (empirical) of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Atomic radius (empirical)</a>: 180 pm</li> <li><a href="../periodicity/rad_cov_single/" title="View molecular single bond covalent radii data for the elements"><img alt="Covalent (single bond) radius on a periodic table spark table" src="data:image/png;base64,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" /> Molecular single bond covalent radius</a>: 169 (coordination number 5) ppm</li> <li><a href="../periodicity/van_der_waals_rad/" title="View van der Waals' radius data for the elements"><img alt="van der Waals radius on a periodic table spark table" src="data:image/png;base64,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" /> van der Waals radius</a>: [ 340 ] ppm</li> </ul> <p><a class="pure-button" href="./atom_sizes.html">More atomc size properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: electronegativities</h2> <ul class="spark_table_list"> <li><a href="../periodicity/eneg_pauling/" title="View definition and pictures showing periodicity of Pauling electronegativity"><img alt="Pauling electronegativity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Pauling electronegativity</a>: 1.5 (Pauling units)</li> <li><a href="../periodicity/eneg_allred_rochow/" title="View definition and pictures showing periodicity of Allred Rochow electronegativity"><img alt="Allred-Rochow electronegativity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" />Allred Rochow electronegativity</a>: 1.14 (Pauling units)</li> <li><a href="../periodicity/eneg_mulliken_j/" title="View definition and pictures showing periodicity of Mulliken-Jaffe electronegativity"><img alt="Mulliken-Jaffe electronegativity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" />Mulliken-Jaffe electronegativity</a>: (no data)</li> </ul> <p><a class="pure-button" href="./electronegativity.html">More electronegativity properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: orbital properties</h2> <ul class="spark_table_list"> <li><a href="../periodicity/ionis_energy_1/" title="View definition and pictures showing first ionisation energies"><img alt="First ionization energy the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> First ionisation energy</a>: 568 kJ mol<sup>‑1</sup></li> <li><a href="../periodicity/ionis_energy_2/" title="View definition and pictures showing second ionisation energies"><img alt="Second ionization energy the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Second ionisation energy</a>: 1150 kJ mol<sup>‑1</sup></li> <li><a href="../periodicity/ionis_energy_3/" title="View definition and pictures showing third ionisation energies"><img alt="Third ionization energy the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Third ionisation energy</a>: 1790 kJ mol<sup>‑1</sup></li> </ul> <p><a class="pure-button" href="./atoms.html">More orbital properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: abundances</h2> <ul class="spark_table_list"> <li><a href="../periodicity/abund_universe/" title="Definitions and pictures showing periodicity of element abundances in the universe"><img alt="Chemical elements abundance by weight in the universe on a miniature periodic table spark table" src="data:image/png;base64,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" />Universe</a>: (no data) ppb by weight</li> <li><a href="../periodicity/abund_crust/" title="Definitions and pictures showing periodicity of element abundances in the earth's crust"><img alt="Chemical elements abundance by weight in the earth's crust on a miniature periodic table spark table" src="data:image/png;base64,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" />Crustal rocks</a>: 0.000010 ppb by weight</li> <li><a href="../periodicity/abund_humans/" title="Abundance in humans of the chemical elements displayed graphically"><img alt="Chemical elements abundance by weight in humans on a miniature periodic table spark table" src="data:image/png;base64,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" />Human</a>: (no data) ppb by weight</li> </ul> <p><a class="pure-button" href="./geology.html">More geological data...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: crystal structure</h2> <figure><img class="pure-img" src="../_media/elements/crystal_structure_image/Pa-sf.jpg" alt="Pa crystal structure"><figcaption>The solid state structure of protactinium is: tetragonal.</figcaption></figure> <p><a class="pure-button" href="./crystal_structure.html">More crystallographic data...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: biological data</h2> <ul class="spark_table_list"> <li><a href="../periodicity/abund_humans/" title="View definition and pictures showing human abundance by weight"><img alt="Human abundance by weight of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Human abundance by weight</a>: (no data) ppb by weight</li> </ul> <p class="p_first">Protactinium has no biological role.</p> <p><a class="pure-button" href="./biology.html">More biological data...</a></p> <div> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>  <ins class="adsbygoogle" style="display:inline-block;width:300px;height:250px" data-ad-client="ca-pub-9334432533380510" data-ad-slot="2897369985"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: uses</h2> <p><a class="pure-button" href="./uses.html">Uses...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: reactions</h2> <p> Reactions of protactinium as the element with air, water, halogens, acids, and bases where known. </p> <p><a class="pure-button" href="./chemistry.html">View reactions of protactinium...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: binary compounds</h2> <p> Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of protactinium where known. </p> <p><a class="pure-button" href="./compounds.html">View binary compounds...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: compound properties</h2> <p> Bond strengths; lattice energies of protactinium halides, hydrides, oxides (where known); and reduction potentials where known. </p> <p><a class="pure-button" href="./compound_properties.html">View compound properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: history</h2> <strong>Protactinium</strong> was <a href="../periodicity/discovery/" title="Further information on element discoveries">discovered</a> by Otto Hahn, Lise Meitner, Frederick Soddy, John Cranston in 1913 at Germany, England. <a href="../periodicity/discovery/" title="Further information on element discoveries">Origin of name</a>: from the Greek word "<em>protos</em>" meaning "<em>first</em>". <p><a class="pure-button" href="./history.html">More history...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="f">Protactinium: isotopes</h2> <div><figure><img class="pure-img" src="../_media/elements/isotopes/isotope_abundance_Pa.png" alt="Isotope abundances of protactinium" /><figcaption>Isotope abundances of protactinium with the most intense signal set to 100%.</figcaption></figure></div> <p><a class="pure-button" href="./isotopes.html">More isotope and NMR data...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-1"> <h2 class="f">Protactinium: isolation</h2> <p class="p_first"> <a href="../periodicity/isolation/" title="literature sources referring to isolation of pure protactinium">Isolation</a>: coming soon!</p> </div> </div>  </main> <div 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