Questions tagged [boiling-point]
The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the 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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Why do azeotropes behave the way they do?
I read this answer to a similar question whilst it proved to be plenty insightful there was this one point I failed to understand:
To get a minimum boiling azeotrope, the deviation from Raoult's Law ...
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Why is the boiling point of SO3 greater than NH3?
NH3 has a net dipole facing upwards towards the nitrogen atom, meaning that it can undergo hydrogen bonding. It also has dispersion forces.
But SO3 has no net dipole as it has a trigonal planar ...
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NO vs NO2 boiling point
Why does $\ce{NO2}$ have a higher boiling point than $\ce{NO}$? They are both polar molecules, but I don't understand what makes them different in b.p. Is it because of the double bond that $\ce{NO2}$ ...
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Surface Tension at Critical Temperature and at Boiling point [closed]
I recently did an experiment on finding the surface tension of a liquid at different temperatures, When I was going through my lab manual, I found the following statement:
As temperature decreases, ...
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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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Why is the relationship between vapour pressure and boiling point of water non-linear?
From my rudimentary understanding of chemistry, pressure should be directly proportional to temperature for a constant mass of gas under the same volume (Charles’s law).
However, in the diagram above,...
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Why does AsH3 have a higher boiling point than HBr?
Aside from the general trend of the boiling points of the hydrides, I noticed how the group 15 hydrides somehow "overtook" the group 17 ones in boiling point, which felt weird.
Notably, H-...
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How does steam distillation work to extract a substance from a mixture, below its boiling point?
This is a small confusion I have regarding steam distillation. Let us consider a sample of water mixed with an organic compound that is insoluble in water. Let us also consider that the boiling point ...
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Boiling point of pentanol isomers
Arrange the following alchohols and alkanes in increasing order of boiling point:
3-pentanol, n-pentane, 2,2-dimethylpropanol, n-pentanol
I understand that n-pentane would have the lowest boiling ...
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Why is octane more volatile than water while having a higher boiling point?
Octane has a boiling point of 120 °C. Water has a boiling point of 100 °C. The definition of boiling point is, "the temperature which the liquid substance's saturated vapor pressure equals the ...
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How can i preserve a coating of baked in powder on activated carbon pellets whenever it rains? [closed]
I'm trying to create pellets of activated carbon that have a coating of a soluble white powder. To make this I first dissolve a significant amount of this powder in boiling water to the point where ...
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Boiling point of 2-methylpyridine is less than that of 3-methylpyridine? [closed]
As I was reading about physical properties of pyridines and substituted pyridines, I came across this:
2-methylpyridine boils at 129°C while 3-methylpyridine boils at 15° higher than 2-methylpyridine
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Is there any solvent I can mix with DMSO to lower its boiling point? [closed]
Is there a way, or a solvent I can mix with DMSO to lower its boiling point?
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Why does N,N-dimethylethanamide have a higher boiling point than butanoic acid?
According to Wikipedia, N,N-dimethylethanamide has a boiling point of $\pu{165.1 °C},$ while butanoic acid has a boiling point of $\pu{163.75 °C}.$
From what I learned, butanoic acid should have a ...
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