Talk:List of elements by melting point

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I have a few problems with this list.

  • The first is that you can not define the melting point of a single atom, nor a single molecule. The melting point depends on the on the chemical and crystalline structure: Carbon exists as Graphite and as Diamond, which can have a different metling point [1]. So one should at least give for which structure the metling point is valid.
  • Secondly the melting point depends heavily on the pressure, if the figures are measured at atmospheric pressure, this should be mentioned.

Donar Reiskoffer 09:19, 13 Nov 2004 (UTC)

I've resorted the list to be by melting point as the title suggests. I've also added some more forms for different elements luckily, amorphous materials should have the same melting point as the most stable form of the element in question, right? Add more forms if you know em… (it turns out I don't have any books with any melting point data on phosphors apart from white for instance. Anybody?)

I've also added the 'standard pressure' specifier, though unlike boiling point, pressure has very little influence on the melting point. --fvw* 07:12, 2004 Nov 21 (UTC)

IIRC, crystalization and allotropic form do result in different physical properties such as melting point. Carbon (as noted) is an example of allotropic effects. May have something to do with the energy locked-up in crystal structures. I imagine, however, that for most things this distinction is meaningless. But hey, I'm no chemist. :) --mav 07:43, 29 Nov 2004 (UTC)

--- Well am not that familiar with the subject, but I do know that ice at the bottom of a glacier melts becuase of the higher pressure. But maybe that is only because of the specific property of water decreasing its density wehn freezeing fro, water to ice. Therefore I think is not useless to mention the pressure. Donar Reiskoffer 12:48, 21 Nov 2004 (UTC)

Water is an exception to almost everthing else in this regard; it does (as you indicate) melt at a lower temperature when under pressure. The reason is due to the fact that liquid water has a smaller volume than ice and pressure reduces volume. So reducing the volume of ice breaks down its structure, thus reverting it to a liquid. This is also how ice skates work. --mav 07:43, 29 Nov 2004 (UTC)

shouldn't temperature be listed in Kelvin?

Probably, also. <nitpick mode>Recent research suggests that ice skating works not because of high pressure but due to molecular surface friction something cohesion mumble mumble something.</nitpick mode> Femto 14:04, 8 Apr 2005 (UTC)

For updating this page I invite to use melting points of the elements (data page) as a reference. Femto 14:04, 8 Apr 2005 (UTC)

Hey everybody isnt magnesium and manganese melting point confused?^^^^Joe F.

I have a more serious problem with this list: It sorts numbers ALPHABETICALLY! i.e. if sorted "higest first": Americium Am 994; Berkelium Bk 986; Sodium Na 98 <---! ; Silver Ag 961; Germanium Ge 938.3, etc.

And +999 temperatures are way down the list! The Boiling pint page seems OK though, so it might be a typo in the code. Can a savvy person fix it? p.s. "Yes, please" to the request for Kelvin p.p.s. yes, if ice melted under the pressure from ice skates then you could just stand still and slowly sink into the ice. :-) I think the pressure does have an effect but not as much as that. 87.81.62.83 13:24, 20 October 2007 (UTC)

contd.------------

Ah, I see - if you keep clicking it it sorts with different modes. Would it be worth giving instructions? 87.81.62.83 18:21, 20 October 2007 (UTC)

  • I have hopefully fixed the temperature sorting using Template:sort - at least with Firefox and Opera browsers it sorts numerically in just two modes: coldest first or hottest first. Now it also has a sortable Atomic number column and shows the Kelvin equivalent, although I don't like the default rounding that the convert template uses.-Wikianon (talk) 03:38, 29 November 2007 (UTC)