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

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What's the melting point of graphite? [duplicate]

I was looking through my textbook and ran over a quite interesting statement regarding graphite: "No melting point, plastically deformable above 2500 °C" So I did some research but didn't really find ...
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Changes in freezing point of sodium acetate

Background: I was recently playing around with some reusable heat packs, the kind that operate by phase change of sodium acetate trihydrate and noticed that they didn't reach the temperature that I ...
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Experimental melting-point of Arm-and-Hammer sodium bicarbonate is remarkably high(?)

Online literature reports the melting point of $\ce{NaHCO3}$ as ~50 deg. C. Using a standard Mel-Temp II melting-point apparatus and a standard alcohol thermometer, I didn't observe any melting of ...
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What happens if you cool water in a container too small for it to freeze?

Freezing a full bottle of water tends to shatter the glass bottle. What if you used something tougher than glass, like diamond? What would happen if you kept dropping the temperature, but restrained ...
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Why do ionic compounds have higher melting and boiling points despite having smaller radii?

Why do ionic compounds have higher melting and boiling points despite having smaller radii? I thought that the closer the two ions are, the larger the repulsive force, and therefore it should rather ...
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Seeking titanium compound, melting point <1600 °C, decomposes to TiO

The title says it all. I’m new to glass making, and I need a titanium compound that will render me $\ce{TiO}$ through decomposition, and has a melting point under 1600 °C. Hopefully I can get one ...
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Boiling/melting points of cyclohexane and cycloheptane

I’m looking at a chart in my book, and while cycloheptane has a higher boiling point than cyclohexane like I’d expect, cycloheptane has a melting point of −12 °C, while cyclohexane has a melting point ...
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Which substance has the highest temperature range between melting and boiling point

Which substances exist that are normally liquid and that will not freeze nor boil even at relatively low/high temperatures as compared to the freezing and boiling points of water? Or how can I ...
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211 views

The effect of air pressure on the “melting point”?

a) No effect b) The melting point increases when the air pressure increases c) The melting point decreases When the air pressure increases The boiling point has inverse relation with ...
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At the eutectic point,what is effect of adding impurity on the melting point?

a) Increase the melting point b) Decrease the melting point c) No effect on melting point It was a question in the test I passed today. I know adding impurity decreases the melting point of a ...
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62 views

Are there compounds that melt under their own weight?

Is there a compound that can melt under its own weight? That is, a block of such material remains solid when put horizontally but starts to melt when put vertically or remains solid in microgravity, ...
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129 views

Why does magnesium have an exceptionally low melting point?

Why does magnesium have a lower melting point than both calcium and beryllium? It does not seem to fit into the group trend.
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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 ...
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Can you melt wood?

We talked about it in our chemistry class but we couldn't get to a conclusion, any help?
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Boiling point and melting point of dihalobenzene compounds [duplicate]

In Dichlorobenzene what explains the boiling and melting point of the 3 structures that can be formed? According to Google The melting point decreases in the order- Para>Ortho>Meta And Boiling ...
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76 views

Household Melting Point Standards

I'd like to accurately calibrate a digital thermometer I'm building in the range $50^\circ$ to $120^\circ$ Celsius. I'm aware that one can buy various chemicals that have melting points in this ...
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Why does the mixture's temperature change while phase transition?

Consider a mixture made up of alcohol and water at room temperature. If I freeze this mixture, why does it change its temperature during the phase change? I don't understand the difference between ...
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129 views

Molecular weight determination from freezing point depression

I have these two questions in my lab manual and I don't know how to approach them. Which is the better solvent for molar mass determinations by freezing point depression, benzene or cyclohexane? ...
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What determines an element’s melting point?

When looking through the periodic table of elements I realized a massive range in the melting and boiling points of the various metals and it seemed to have nothing to do with its elemental number, ...
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71 views

How do we predict the order of melting points of group 1 and group 2 halides?

I get really confused by this: The order of melting points of group 2 chlorides is: $$\ce{BaCl2 > SrCl2 > CaCl2 > MgCl2 > BeCl2}$$ This is completely understandable by Fajan's Rules. ...
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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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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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Boiling and melting point of trans- and cis-but-2-ene

The boiling point of trans-but-2-ene is lower than that of its cis isomer but the melting point of the former is higher than the later. Why is it not following the same order? Is there any factor of ...
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How to rationalise the difference in the melting points of acids and alcohols with inter molecular forces?

Acids: arachidic acid, palmitic acid, lauric acid, etc. Alcohols: butan-1-ol, pentan-1-ol, etc. The melting points of acids with $\ce{-COOH}$ at the end compared to melting points of alcohols, ...
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Can powdered beta-tin be made from raising the temperature of alpha-tin?

When white tin ($\beta$-tin) is cooled to a temperature below $13.2\ \mathrm{^\circ C}$, it creates the allotrope of gray ($\alpha$-tin), a gray, amorphous powder. My question is that once you have ...
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390 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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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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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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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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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 (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 ...
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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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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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1answer
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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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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 ...