Talk:Melting point

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The melting point is 100'C

Contents 1 melting vs. freezing point 2 Tungsten doesnt have the highest melting point of all elements 3 Crystalline solids only? 4 Pure Substance

[edit] melting vs. freezing point

I'm not sure whether the melting point is for all substances the equivalent of the freezing point as stated in this article.

• you are correct in fact. for example, agar solidifes at ~55C but melts at a higher temperature. i will work on this later when i have the time because it is very important. good find. -- Bubbachuck 17:49, 12 August 2005 (UTC)

• • Done. Bubbachuck 22:39, 13 August 2005 (UTC)

This same problem exists in the article for Melting, where I flagged it awhile back. Would you fix it there, too, please and remove my dubious flag from that article. Thanks. PS. Someone else noticed it in this article. I sign my posts. 5Q5 14:39, 13 March 2007 (UTC)

[edit] Tungsten doesnt have the highest melting point of all elements

Tungsten doesnt have the highest melting point of all elements, it has the highest melting point of all metals. Carbon (melting point of 3823 K) has the highest melting point of all elements. However, Tungsten does have the highest boiling point. —The preceding unsigned comment was added by 24.242.200.33 (talk • contribs) 10:31, 7 February 2006 (UTC).

Carbon at ambient pressure does not melt but sublimates. A liquid phase only exists above 10 MPa. Femto 13:27, 7 February 2006 (UTC)

If we don't restrict this to elements and allow compounds, there's tantalum hafnium carbide (Ta₄HfC₅) with a m.p. of 4215 °C [1]. (Note though that even Britannica weasels around calling it "the" highest.) Femto 13:27, 7 February 2006 (UTC)

[edit] Crystalline solids only?

Message from OTRS: "The melting point is a characteristic of only crystalline solids, not all solids."

Amorphous solid materials may have a glass transition to which a fictive temperature can be attributed but many do not have even that.

[edit] Pure Substance

"The melting point of a pure substance is always higher than the melting point of that substance when a small amount of an impurity is present." Is this really true? Does it need qualification? Is this related to the unexplained phrase "melting-point depression" mentioned on the Lauric acid page? --Elijah 20:59, 25 August 2006 (UTC)

"Yes as far as I know and also based on first principles", "I don't think so", abd "exactly", respectively. Melting point depression is the phenomenon that impurities lower the melting point of a pure substance. DMacks 16:13, 28 August 2006 (UTC)

Then could someone more knowledgeable about the subject include that here in a way that articles like the lauric acid one could link to it? --Elijah 05:21, 29 August 2006 (UTC)