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Questions tagged [melting-point]

The melting point of a solid is the temperature at which it changes state from solid to liquid.

At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends (usually slightly) on pressure and is usually specified at standard pressure.

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How do you melt metals with super high melting points?

At the Renaissance fair a few years back I was watching a smith forge metal into shapes. During this time a very odd question came to me. I was wondering what the furnace was made of. My logic stated that whatever the furnace was made of must have a…
Griffin
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Why is the melting point of p-toluenesulfonic acid monohydrate higher than that of anhydrous p-toluenesulfonic acid?

Why is the melting point of p-toluenesulfonic acid monohydrate higher than that of anhydrous p-toluenesulfonic acid? Compare for example the melting point of benzenesulfonic acid hydrate, which is lower than for anhydrous benzenesulfonic acid.
Henry
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How could uranium be extracted from ore to be melt?

I would like to go hunting for uranium ore, and because it has a relatively low melting point (1132.2 °C), I thought it would be cool to melt it just like any other metals. According to this video extracting yellowcake (mainly U3O8, UO2 and UO3) is…
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Melting points of NaCl and RbCl

Why is the melting point of $\ce{NaCl}$ more than that of $\ce{RbCl}$ ? Using Fajan's Rule of polarizing power, $\ce{RbCl}$ has more ionic character and thus should have a higher melting point.
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Why does magnesium have the lowest melting point of all earth alkalis?

Why does magnesium have the lowest melting point of all earth alkali metals?
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Substance of higher latent heat of melting than water, similar melting point

I saw ingeniously simple "cooler box" yesterday - a double-walled plastic box with some liquid between the walls. You freeze it, and it keeps temperature near the freezing point of that liquid, until the liquid melts, while you can store dry foods…
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Lowest freezing point room temperature liquid?

What substance that is liquid at STP has the lowest freezing/melting point? I think it's either 2-methylpentane or 3-methylpentane, but I get different numbers from different sources.
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Avoiding snow melting with salt

I've been quite stunned during the last Winter Olympics in Sochi by the following fact. Temperatures were quite high, sometimes 10° Celsius, and the organizers had to do something to prevent the snow from melting. I heard on the TV the commentators…
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Why is the pure tungsten (W) melting point higher than that of its oxides (either WO3 or WO2)?

Why is the pure tungsten ($\ce{W}$) melting point way higher than that of its oxides $\ce{WO3}$ or $\ce{WO2}$? And why does pure $\ce{Al}$ react differently? I.e. the oxides have a higher melting point than pure $\ce{Al}$.
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How do scientists study liquid tungsten?

Inspired by this What If article: https://what-if.xkcd.com/50/ In the above article, Randall Munroe mentions that liquid tungsten is difficult to study because of its extremely high melting point. Because of this property, containers for the…
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Which melting point would indicate a metallic structure?

Question If you have three substances with three different melting points; 445 °C 1907 °C -7 °C Which of these would most likely have a metallic structure? I understand that the third option would most likely be covalent. But between the first…
Sid
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Does granite become soft as modelling clay at 2000 °C?

As Wikipedia tells us, it consists of $\ce{Al2O3}$ ($14.42\%$) (alumina) whose melting point is $\pu{2072^\circ C}$, and $\ce{SiO2}$ ($72.04\%$) (silica) whose melting point is $\pu{1713^\circ C}$. So does it soften to modelling clay (or at least…
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Pure gallium with lower melting point?

I melted about 2 kg of gallium and put it in a plastic container, in order to make crystals. After letting them grow and extracting them, I let the gallium freeze at the room temperature, which is below the melting point. However, for some reason…
user81153
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Why is the melting point of iodine so high compared to ammonia? What about Zn and C(diamond)?

Increasing order of melting point by searching the temperature on the web: $$\ce{NH3} <\ce{I2} <\ce{Zn}<\ce{C_{diamond}}.$$ The idea I have read on "Chemistry: The Central Science" by Theodore L. Brown, ‎H. Eugene LeMay Jr., ‎Bruce E. Bursten on…
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Applying salt to roads to melt ice--is it special?

Most everyone is familiar with applying salt to the roads during winter to melt ice. I'm wondering if there's anything special about placing salt on the roads or would any other substance, sand for example, work equally well in melting the ice.
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