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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Question regarding enthalpy of sublimation vaporization and fusion
While learning Thermochemistry, I came across the formula
$\Delta H_{sub} = \Delta H_{vap} + \Delta H_{fus}$
Now my question is how that when we want to change the phase of a substance from solid to ...
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Does gunpowder (black powder) melt when heated?
I was just watching a video about yellow powder (similar formula to black powder, but with potassium carbonate instead of charcoal), and I was wondering:
Does regular black powder melt (and ...
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Why DMSO has much higher freezing point than DMF (19 °C vs -61 °C)?
Recently, while solvent optimization of a reaction, I found DMSO froze in an ice-bath but DMF didn't.
From Wikipedia, I found out that DMSO (dimethyl sulfoxide) has a freezing point of 19 °C (ref. 1) ...
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Why does pectin/agar jelly taste sweet, if they stay solid at 36.5 °C, entrapping sugar?
When we eat pectin jelly(fruit jelly) or agar jelly, they taste sweet.
This should imply that sugar entrapped in gel network is somehow exposed and dissolved to saliva.
However, pectin and agar gel ...
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Melting Point Order of Benzene Derivatives
Q)Compare the melting points of the following?
o-Hydroxybenzaldehyde
o-Methoxybenzaldehyde
p-Hydroxybenzaldehyde
p-Methoxybenzaldehyde
My attempt: Intermolecular H-bonding increases melting point ...
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Melting point of sulfur
The melting point (m.p.) of rhombic sulfur is 385.8 K while the m.p. for monoclinic sulfur is 392 K. Also, the transition temperature of rhombic to monoclinic sulfur is 369 K.
Now, consider heating ...
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Wide temperature range fluids
I am investigating various fluid power compounds for use at high temperatures. I am seeking a material that is liquid around room temperature, or melts at under 300 C, but that remains a stable liquid ...
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Alkali-rich lead glass with working range at room temperature
I understand that the glass transition temperature (above which it is considered a super-cooled liquid) is quite far below the liquidus of the corresponding crystalline mixture. In the paper, "...
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Why is that during a phase transition, a single melting point exists for melting?
I know that during melting, latent heat is used in increasing potential energy (as intermolecular distance increases) of the complete structure of given solid to liquid. But it can also happen ...
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What explains the relative order of melting and boiling of oxygen and nitrogen?
Why is the melting point of nitrogen ($\ce{N2}$) greater than that of oxygen ($\ce{O2}$)? After all, both are non-polar, and $\ce{O2}$ has more electrons than $\ce{N2}$.
In addition, why is the ...
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How would you explain the general trend in melting point between Group 1 and Group 2 chlorides?
This question is based off of the attached chart. I notice how there's a general increase in melting point down group 2 chlorides and a general decrease (except for Lithium) down the group 1 chlorides....
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Why exactly does copper have a higher melting point than zinc?
It is said that copper has a higher melting point than zinc because of the d electrons in copper being involved in metallic bonding. However, copper has no unpaired electrons in its d subshell just ...
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Why is the melting point of meta-diiodobenzene higher than that of ortho-diiodobenzene?
I'm currently trying to reason for as why the melting point of meta-diiodobenzene higher than that of ortho-diiodobenzene and I'm unsure of what to say. I understand the para isomer has the highest ...
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Neopentane melting point [duplicate]
Given that neopentane and n-pentane are both hydrocarbons derived from pentane with five carbon atoms each, but differ in their structural arrangements — with neopentane being more branched and n-...
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Why does the melting point of hexafluorosilicic acid differ that much in these two solution concentrations?
From the Wikipedia article for hexafluorosilicic acid:
Melting point:
ca. 19 °C (66 °F; 292 K) (60–70% solution)
$<$ −30 °C (−22 °F; 243 K) (35% solution)
What's the reason for this huge ...
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