Questions tagged [melting-point]

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

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Is there a metal that melts and solidifies quickly?

Is there any kind of metal that melts very quickly with very low heat or temperature, and at the same time, becomes hard very quickly?
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Why is the melting point of p-dichlorobenzene higher than those of o-dichlorobenzene and m-dichlorobenzene?

I was going through alkyl and aryl halides and noted the following statement in my textbook: p-dichlorobenzene has higher melting point and solubility than those of o-dichlorobenzene and m-...
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Why does silicon tetrafluoride have a higher melting point than sulfur tetrafluoride?

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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What would explain urine that resists freezing?

A frozen urine specimen is required for an organic acids lab test, but the urine refuses to freeze after 4 days in a regular freezer turned as low as it will go. What would explain this, and how cold ...
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What is the melting point of diamond?

Textbooks and the online reference differ about this and there are more than two answers.
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Caffeine boiling and melting points

According to both caffeine's PubChem page and ChemSpider page its boiling point lies at $\pu{173 °C}$ and its melting point at $\pu{\sim 235 °C}.$ How can it melt at that temperature if it already ...
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Melting points and boiling points of primary alcohols do not follow the same trend

If one considers boiling points (in °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 Van der Waals forces ...
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Is there a correlation between the susceptibility of a polymer to undergo hydrolysis and its melting point?

As per topic, I was wondering why the Tm of the polymers PGA, PLA and PLGA are in the following order. Does it correlate to their ability to undergo hydrolysis? PGA>PLA>PLGA
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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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What is the effect of adding salt to ice?

What will happen to the melting point temperature of ice if some common salt is added to it? How to justfy the answer?
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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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Melting and boiling points of transition elements

The melting and boiling points of transition elements increases from scandium ($1530~\mathrm{^\circ C}$) to vanadium ($1917~\mathrm{^\circ C}$). They increase because as we go across the group, we ...
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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 $\mathrm{d}$-block. If I take for ...
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Why do 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 so?

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