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

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Can powdered beta-tin be made from raising the temperature of alpha-tin?

When white tin ($\beta$-tin) is exposed to temperature below 13.2$^o$ C it creates the allotrope of gray ($\alpha$-tin), a gray amorphous powder. My question is that once you have the powdered gray ...
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101 views

How to RAISE the melting point of water?

It is common that adding common salt into water will lower its melting point. But, is there any way to RAISE the melting point of water? Does it lower the boiling point of water as well? Why?
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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 ...
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Effect of inductive effect on boiling point,melting point and dipole movement

In my book the following was written:- Inductive effect is a permanent effect operating in the ground state of the organic molecules and hence is responsible for higher melting point, boiling ...
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71 views

Is there a material that reduces copper melting point and completely dissolves?

Is there any material that you mix/alloy with copper that will result in something that behaves similar to plastic (that is at room temperature it is solid, at maybe 500K or similar it can be easily ...
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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 ...
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Material that doesn't melt at 800 deg F, but can be dissolved?

I'm a sculptor and I have a chemistry/plastic question. I thought here would be a good place to ask. I'm looking for a substance (probably a plastic) that has these characteristics: Doesn't melt at ...
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64 views

What happens when ice melts?

What happens when ice melts? I have this question, with two possible answers: regularly arranged molecules change into irregularly arranged molecules water molecules become less densely packed ...
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Are forming coins starting with sodium chloride possible without the clay melting from the molten metal?

Is forming metal coins (specifically ones with copper, nickel, and zinc) possible with these steps: Carve a sheet of sodium chloride so that it is big but not too big and so that the design sticks ...
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160 views

The highest melting point

Inspired by this question, what is the substance or compound with the highest melting point? At standard atmospheric pressure and ever-increasing temperature which substance a) eventually becomes ...
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Which compound has the highest melting point?

Which of the following compounds has the highest melting point : $\ce{PCl5}$, $\ce{H2O}$, $\ce{NaCl}$, $\ce{SrCl2}$, $\ce{CaF2}$? I've asked a question concerning the boiling points and I got an ...
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Is melting of gold a physical property?

I read that melting of gold is a physical property, but I wonder if this is true. If we want to melt gold we will need to add heat, and once we add heat to gold to melt it, there must be a chemical ...
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How to calculate melting/boiling points at different pressures

I know water boils at below room temperature in a vacuum, and want to know if there's an equation to calculate the melting or boiling points of elements or compounds at a given pressure. How would I ...
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Will heating alumina (Al2O3) to its melting point yield pure Al?

My inorganic chemistry is at a basic level, so my question is, if I heat alumina ($\ce{Al2O3}$), to its melting point around 2000 C, will I wind up with pure Al? I think the oxygen will release from ...
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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 ...
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A metal that melts quickly?

Is there a kind of metal that melts very quickly with very low heat or temperature and at the same time becomes hard very quickly? I'm very naive in chemistry with limited knowledge. So I hope your ...
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1answer
719 views

Why does SiF4 have a higher melting point than SF4?

So looking at the Wikipedia pages of sulfur tetrafluoride and silicon tetrafluoride, the melting points are -121 °C and -90 °C respectively, and so $\ce{SiF4}$ has the higher melting point. However, ...
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Does supersaturated caffeine polymerize?

I tried preparing a supersaturated solution of caffeine by mixing anhydrous caffeine powder with water in a thin Turkish tea glass and heating it up over a candle (desperate times...). This worked ...
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Caffeine boiling and melting points

According to both caffeine's pubchem page and chemspider page its boiling point lies at 173°C and its melting point at ~235°C. How can it melt at that temperature if it already sublimated at 173°C? Or ...
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Melting points and boiling points of primary alcohols do not follow the same trend

If one considers boiling points ($^{o}C$) of primary alcohols, one finds the following: methanol: 65 ethanol: 79 1-propanol: 97 1-butanol: 117 1-pentanol: 138 This trend is due to Wan der Waals ...
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Superheating metal alloy above solidus

Is it possible to heat a material above its solidus without melting occurring? More specifically, at a heating rate of approximately 200K/s, will a metal alloy exhibit superheating and if so by what ...
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257 views

Specific latent heat of fusion of a noble gas

Could someone explain to me where the additional energy goes when applied to an object in the state of melting (such as water) so that the temperature of the object does not increase, and could ...
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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 ...
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Materials that resist adhesion with molten glass even when hot

I'm looking for ways to manipulate molten glass with (e.g. bending a heated glass tube). This article mentions that oxides tend to adhere, hence molten glass to heated stainless steel. What ...
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1answer
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Why does chocolate ice cream melt faster than others?

The other day I was dipping out Neapolitan(strawberry, vanilla, & chocolate) ice cream and noticed that the chocolate ice cream tended to melt faster than that of the vanilla and strawberry. I ...
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How did Michael Faraday melt Sodium Chloride?

Michael Faraday melted sodium chloride in a silver spoon and ran an electric current through the molten salt, which released chlorine as a gas and left pure sodium behind. Sodium chloride melts at ...
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What is the difference between melting and dissolving?

What is the difference between melting and dissolving? I am looking some general features. The answer should be adaptable to the melting/dissolving of ice cube (water) in a class of pure alcohol ...
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What makes some metals melt at higher temperature?

I'm looking at the melting temperature of metallic elements, and notice that the metals with high melting temperature are all grouped in some lower-left corner of the $d$ block. If I take for example ...
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Why do any impurities lower the melting point of an isolated substance?

It is known that impurities in a desired isolated product lower the melting point of the mixture, even if the impurities melting point is much higher than the desired product. Why is that?