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		<id>https://www.explainxkcd.com/wiki/index.php?title=2719:_Hydrogen_Isotopes&amp;diff=304008</id>
		<title>2719: Hydrogen Isotopes</title>
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				<updated>2023-01-03T15:23:46Z</updated>
		
		<summary type="html">&lt;p&gt;Dbrahm: In the Transcript, Instant Hydrogen is &amp;quot;A single neutron&amp;quot;, not &amp;quot;A single proton&amp;quot;.&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{comic&lt;br /&gt;
| number    = 2719&lt;br /&gt;
| date      = January 2, 2023&lt;br /&gt;
| title     = Hydrogen Isotopes&lt;br /&gt;
| image     = hydrogen_isotopes_2x.png&lt;br /&gt;
| imagesize = 442x250px&lt;br /&gt;
| noexpand  = true&lt;br /&gt;
| titletext = Oops, All Neutrons is also known as Neutral Quadrium, Nydnonen, and Goth Tritium.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
{{incomplete|Created by a BREAK ROOM DE BROGLIE MICROWAVE USER. Do NOT delete this tag too soon.}}&lt;br /&gt;
&lt;br /&gt;
{{W|Hydrogen}} is the simplest of the chemical atoms, usually consisting of an electron orbiting an proton. This comic imagines other humorous fictional forms of hydrogen as follows:&lt;br /&gt;
&lt;br /&gt;
{| class=&amp;quot;wikitable&amp;quot;&lt;br /&gt;
! &amp;quot;Isotope&amp;quot;&lt;br /&gt;
! Real?&lt;br /&gt;
! Description&lt;br /&gt;
|-&lt;br /&gt;
|Hydrogen&lt;br /&gt;
|Yes&lt;br /&gt;
|Hydrogen is the most common {{w|isotope}} of hydrogen, with one proton and one electron, shown with the electron orbiting the proton. It is also known as protium.&lt;br /&gt;
|-&lt;br /&gt;
|Deuterium&lt;br /&gt;
|Yes&lt;br /&gt;
|{{w|Deuterium}} is the second most common isotope of hydrogen, with one electron and both a neutron and proton in its nucleus. About one of every 6,760 hydrogen atoms in seawater is deuterium.&lt;br /&gt;
|-&lt;br /&gt;
|Tritium&lt;br /&gt;
|Yes&lt;br /&gt;
|{{w|Tritium}} is the third most common isotope of hydrogen, with one electron and a nucleus of one proton and two neutrons, for an atomic mass of about three {{w|Dalton (unit)|daltons}}. It is radioactive with a half-life of about twelve years, and is very rare (but not as rare as unbound &amp;quot;instant hydrogen&amp;quot; neutrons.)&lt;br /&gt;
|-&lt;br /&gt;
|Ium&lt;br /&gt;
|Not as such&lt;br /&gt;
|This imaginary isotope consists of one electron orbiting around nothing. The name relates to the fact that the two heavier isotopes are named from a prefix designating the number of {{w|nucleons}} followed by the suffix &amp;quot;-ium&amp;quot;, which is sometimes used satirically, e.g., in &amp;quot;unobtainium.&amp;quot; Free electrons are always in motion, {{w|Fermi energy|even at absolute zero temperature}}, but not in stationary orbits.&lt;br /&gt;
|-&lt;br /&gt;
|Wheelium&lt;br /&gt;
|No&lt;br /&gt;
|This fictional form consists of a proton, electron, and neutron orbiting around nothing, shaped similarly to a wheel. The neutron would either bind to the proton, or much more likely, be {{w|Elastic_scattering#Nuclear particle physics|elastically scattered}} away.&lt;br /&gt;
|-&lt;br /&gt;
|Instant hydrogen (ready in 15 minutes)&lt;br /&gt;
|Yes, but rare&lt;br /&gt;
|This is just a single neutron. Unbound neutrons will take about fifteen minutes to decay into a proton, an electron, and a neutrino. The neutrino will carry away momentum, while the proton and electron ''can'' form into a hydrogen atom. However, this [https://van.physics.illinois.edu/ask/listing/1207 only happens about four times in a million] (though the proton could also capture another electron). The name is likely a reference to &amp;quot;instant&amp;quot; meals (e.g. instant noodles) which are typically reduced in form for convenient storage, and can be simply reconstituted into their usable form.&lt;br /&gt;
|-&lt;br /&gt;
|Hydrogen (maximum strength)&lt;br /&gt;
|No&lt;br /&gt;
|This fictional isotope consists of a proton, an electron, and what appear to be at least 14 neutrons. This isotope's proton would not be bound to all the neutrons. It would immediately decay by {{w|Nuclear drip line|dripping}} most all of them away.&lt;br /&gt;
|-&lt;br /&gt;
|Oops, All Neutrons&lt;br /&gt;
|Maybe&lt;br /&gt;
|This fictional form consists of four neutrons, a {{w|tetraneutron}}, with one orbiting around a group of three. The name is likely a reference to an American breakfast cereal called {{w|Cap'n Crunch#Variations|Oops! All Berries}}.&lt;br /&gt;
&lt;br /&gt;
The title text provides three other names of this form: 1. &amp;quot;Neutral Quadrium&amp;quot;: [https://www.yourdictionary.com/quadrium Quadrium] is a rare but real isotope of hydrogen consisting of one proton and three neutrons (the &amp;quot;quad-&amp;quot; prefix designating its four nucleons). The proton and electron in quadrium have both been replaced with neutrons, making this fictional atom neutral. 2. &amp;quot;Nydnonen&amp;quot; is likely a derivation of &amp;quot;hydrogen&amp;quot; with three of its consonants replaced with the letter 'n' so it has four of them representing the four neutrons. 3. &amp;quot;Goth Tritium&amp;quot;: All the particles in the depiction are black, resembling stereotypical {{w|gothic fashion}}, and in the same configuration as the particles of tritium.&lt;br /&gt;
|}&lt;br /&gt;
&lt;br /&gt;
{{notice2|The Mountain View, California Public Library is hosting an online chat with [[Randall Munroe]] Tuesday, January 31 at 11am Pacific.&amp;lt;br/&amp;gt;[https://libraryc.org/mountainviewlibrary/22032 Register here to send your question(s) to the moderators.]|image=Crystal Project Agt announcements.png}} &amp;lt;!-- pending admin request to add blurb to sitenotice --&amp;gt;&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
:[Eight drawings of different versions of hydrogen atoms are shown. They are arranged in two rows of four. The depictions use the planetary model version with for instance a negative electron (with a &amp;quot;-&amp;quot; written inside a small circle) orbiting a positive proton (with a &amp;quot;+&amp;quot; written inside a larger circle) and a black neutron depicted as a circle of the same size as the neutron, as in the second atom - Deuterium. Each has a label underneath. Here, they are listed in reading order:]&lt;br /&gt;
:[An electron orbiting a proton:] &lt;br /&gt;
:Hydrogen&lt;br /&gt;
&lt;br /&gt;
:[An electron orbiting a proton connected with a neutron:] &lt;br /&gt;
:Deuterium&lt;br /&gt;
&lt;br /&gt;
:[An electron orbiting a proton connected with two neutrons, so they form a triangle:] &lt;br /&gt;
:Tritium&lt;br /&gt;
&lt;br /&gt;
:[An electron orbiting nothing:]&lt;br /&gt;
:Ium&lt;br /&gt;
&lt;br /&gt;
:[An electron a proton and a neutron all orbiting on the same circle around nothing. They are placed equidistant from each other forming a large triangle:]&lt;br /&gt;
:Wheelium&lt;br /&gt;
&lt;br /&gt;
:[A single neutron:] &lt;br /&gt;
:Instant Hydrogen (ready in 15 minutes)&lt;br /&gt;
&lt;br /&gt;
:[An electron orbiting a proton connected with many neutrons, 13 visible with six  touching the proton which are in front. Four more are close to those six and mostly shown and then three are only just visible behind the others. Looking closely there are also two smaller dots near the edge indicating at least two more, for 15 that can be seen. And several more would be behind the visible neutrons if this forms a spherical shape. The electrons orbit just barely goes around the outer neutrons:] &lt;br /&gt;
:Hydrogen (maximum strength)&lt;br /&gt;
&lt;br /&gt;
:[Four neutrons arranged like the particles in Tritium with a neutron orbiting a triangle of neutrons.]&lt;br /&gt;
:Oops, all neutrons&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&lt;br /&gt;
&lt;br /&gt;
[[Category:Charts]]&lt;br /&gt;
[[Category:Physics]]&lt;br /&gt;
[[Category:Chemistry]]&lt;/div&gt;</summary>
		<author><name>Dbrahm</name></author>	</entry>

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