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

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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 ...
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Melting point of ocean salt: eutectic?

I'm interested in the melting point of ocean salt. While sodium chloride has a melting point of 801 °C, ocean salt contains 15 % other ions, mainly sulphate, magnesium, calcium and potassium (the ...
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Melting points of alkali metal halides

The correct order of melting point of alkali metal halides is: $\ce{MF}>\ce{MCl}>\ce{MBr}>\ce{MI}$ $\ce{MI}>\ce{MBr}>\ce{MCl}>\ce{MF}$ $\ce{MCl}>\ce{MF}>\ce{MBr}>...
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Order of melting points of Compounds [duplicate]

I don't get the order of melting points of the ortho, para and meta isomers of dichlorobenzene. My book says that the order of melting points is para-isomer > ortho-isomer > meta-isomer. Now, I get ...
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Melting and boiling point trend in Group II

The following picture shows the melting and boiling point trends down group II elements. I have added question marks where the variability in data was rather disturbing (over two hundred degrees ...
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best metal for mini turbine exhaust blade (i.e. drone)

Based on research I find that all turbine blades for major airlines are titanium with nickle alloy at turbine closest to the fire chamber. But I don't necessarily have all the resources available to ...
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25 views

Manipulate melting point of frozen water [duplicate]

How to manipulate water in way that ice melting point isn't 0°C, but for example 4°C?
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47 views

Intermolecular Forces in Teflon vs Polyethylene

From Wikipedia, polyethylene has a melting point of around $400K$, while Teflon (polytetrafluoroethylene) has a melting point of $600 K$, which is much higher. Besides the increased London Dispersion ...
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Assumptions made in calculating melting point from thermodynamic data

I'm fine with doing these questions, such as: For ammonia, enthalpy of fusion is 5.65 kJ/mol, and entropy of fusion is 28.9 J/K.mol Hence find an approximate melting point: Well $\Delta G = \Delta H ...
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38 views

Structure of crystals vs melting point

Calcium oxide has a melting point of 2700C and sodium chloride has a melting point of 801C, if they have the same crystal structure and ions are about the same distance in each crystal why is there ...
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Melting temperature and electronegativity trends in transition metals [duplicate]

So I know that generally the melting temperature increases across the row (let's look at just the first row for now) but what are the deviations? And why do they occur? I've looked everywhere online ...
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Liquifying metal and toxic fume exposure

I just read a very entertaining Youtube comment thread on a video where TheBackyardScientist melts tin on the stove in his (enclosed) kitchen, the proceeds to cook a steak on it. According to the ...
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What is the melting point of glycerol in a vacuum?

Can anyone tell me what the melting point of glycerin would be in a vacuum? From researching online (disclaimer: I'm definitely not a chemist) it seems the boiling point is ~170 °C in a vacuum (vs. ~...
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How do covalent crystals melt?

A network solid, like diamond or silicon dioxide, has a lattice of covalent bonds that make up a giant structure. Normally when you melt a simple molecular substance, you are breaking the inter ...
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76 views

Melting point-general chemistry

This one has stumped me for a few days. What is the specific name of the general chemistry principle that is responsible for the difference in melting points of pure and impure solids. I have ...
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188 views

How does ice melt?

I know that when water freezes, it forms a crystalline structure created by the hydrogen bonds between polar water molecules. Also, I know that during a phase change, the potential energy of the ...
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Would a melted crystal recrystallize back into the same lattice structure when frozen?

Two things that I'm not sure about melted crystals: For a material that has only one possible crystal structure, would freezing cause it to recrystallize, or could it become amorphous upon freezing? ...
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348 views

Sodium chloride and melting of the ice

My question is this, In European countries, they use NaCl or KCl to melt ice during the winter season. In Asian Countries, they use NaCl to keep the ice without melting. (Ex- Ice cream boxes, Beer ...
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Is it possible, given a target temperature, to create an alloy that melts at precisely that temperature?

Assuming the target melting points are between the melting points of mercury and tungsten, is it possible, given a target temperature, to create an alloy (or compound) composition that has a direct (...
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420 views

Why does the boiling and melting point decrease as you go down group 1 and vice versa for group 7?

I used to think that because an alkali metal needs to lose one electron to complete its outer shell, when the atom increases in size (atomic radius), the electron would be easier to lose as the ...
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At what temperature (in kelvin) are most of the elements on the periodic table liquids?

This question is out of pure curiosity. At what temperature are a majority of the elements on the periodic table in a liquid state/phase of matter? For the purpose of this question, assume the ...
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How to create liquid carbon, and what kinds of properties does it have? [duplicate]

Carbon sublimes at about 3915K. In a high pressure environment, shouldn't it be possible to create liquid carbon at high temperatures? Has this ever been done? What does it look like and what ...
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42 views

Why there is a non-linear trend on the melting points for period 2 elements, especially Na to Si?

Using the knowledge of periodicity from high school cannot explain this, what it tells me is just metallic bonding. The model of delocalised electron from a metallic lattice can explain the increase ...
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367 views

Why do the melting points of Group 15 elements increase upto Arsenic but then decrease upto Bismuth?

The boiling points of group 15 elements increase on going down the group (or, as size increases) but the same is not true for the melting points. The melting points increase from $\ce{N}$ to $\ce{As}$ ...
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Why does melting point depend on external pressure?

The melting point of a substance is the temperature at which the solid form's vapor pressure equals the liquid form's vapor pressure. I read that the vapor pressure of something depends ONLY on the ...
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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 are the melting points of Sb and Bi lower than that of As?

My book says it has something to do with the inert pair effect. And unlike As, Sb and Bi tend to form 3 covalent bonds rather than 5. I don't understand what's really going on here.
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Can I melt Barium Titanate powder into a cylinder and preserve the high dielectric?

I would like to make various solid forms of Barium Titanate e.g. cylinders, discs. Barium Titanate powder seems widely available and has a melting point of 1,625'C. Can I melt it in an iron forge ...
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350 views

Why is Iodine's melting point is lower than water?

My teacher told us that melting point of Iodine is lower than Ice as it is a Simple molecular structure bonded by weak van der waals forces. However I gooogle and found out its melting point is 113.7°...
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74 views

What is the melting point of HfS2, HfSe2, ZrS2, ZrSe2?

I am currently working on these materials ($\ce{HfS2, HfSe2, ZrS2, ZrSe2}$) and I need to know the melting temperatures of these compounds before starting my work. Has anybody found the melting ...
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197 views

How to calculate the boiling point of a solid substance?

Say that I have a solid substance; I know its density, mass, volume, melting point, specific heat, the pressure which it is under, and nothing else. (for now.) How do I find the heat at which it ...
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Can you call a table frozen?

Someone has argued that the table sitting in front of us is 'frozen'. I do agree that the table has a freezing point. The table has a melting point, but that is beyond the ignition point and the ...
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Why there is an exception in melting and boiling point in p block?

Why is the boiling point and melting point of 15th group and 16th group has an exception? As we know that as molecular mass increases boiling point and melting point will also increase. So on going ...
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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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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 vapor ...
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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 ...
6
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1answer
81 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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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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Predicting melting points of substances based on their molecular/atomic structure

Wouldn't it be great to be able to predict the melting point of a metal based on the atomic number and not by looking in some table for the value that was measured experimentally by someone else? Or ...
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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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Why/How am I calculating freezing point depression wrong?

What is the freezing point of water made by dissolving $\mathrm{10.11~g}$ of magnesium chloride in $\mathrm{86.03~g}$ of water? The freezing-point depression constant of water is $\mathrm{1.86~^\...
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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 ...