All Questions
Tagged with intermolecular-forces melting-point
24 questions
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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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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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What happens to the sea of electrons when a metal melts/boils? [closed]
I was taught about metallic solids with the sea of electrons model. My question is how does the sea of electrons function when metal turns into a liquid and a gas. The way I see a liquid is ...
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Why does diethylmethylamine have such a low melting point?
According to PubChem, diethylmethylamine has a remarkably low melting point of $-196.0\ \mathrm{^\circ C}$. This is substantially lower than the melting points of dimethylethylamine ($-140.0\ \mathrm{^...
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Why does roasting requires lower temperature than melting point
Why do processes like roasting and calcination require a temperature lower than the melting point? Since intermolecular forces are lower in a liquid won't it be easier to oxidise (roasting) / ...
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Freezing point vs Intermolecular forces
Water has a higher boiling point (100°C) than cyclohexane (81°C). This is probably because of stronger intermolecular forces between water molecules as compared to cyclohexane molecules. Then, why is ...
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Which has a high melting point, cocoa powder or cocoa butter?
I have been doing some research into chocolate, and after looking at the chemical compositions of cocoa butter and cocoa powder, struggled to determine which had a formula/structure that would have a ...
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What effect on boiling and melting points does intramolecular hydrogen bonding have? [duplicate]
I know that intermolecular forces increase the boiling and melting point of a compound, but what is the effect of intramolecular forces on boiling and melting points?
I found contradicting answers ...
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How to know if a sample suffered descomposition during melting point? [closed]
If I take a sample in order to determine its melting point, how do I know if that sample suffered a descomposition?
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For two compounds that are symmetrical, why does the more compact one have a higher melting point?
In this post, I refer to two molecules B (Di-tert-butyl ether) and C (Dibutyl ether).
Wikipedia: Di-tert-butyl ether (B)
b.p. 107.2 C
m.p. - 61 C
...
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If we start heating a substance, does it melt when we break its intermolecular bonds? [closed]
I was reading the 2 following posts:
Do substances melt when we break their intermolecular bonds?
Is melting/boiling point of ionically bonded substance higher than of covalently bound?
Altough ...
17
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Why is the melting point of PCl3 less than that of PCl5?
From just the IB chemistry bonding chapter information, you would normally deduce that $\ce{PCl3}$ and $\ce{PCl5}$ are both covalent molecules.
However, as $\ce{PCl3}$ has a dipole moment, it has ...
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How do you tell which molecule has a higher melting point?
In the instance of comparing $\ce{NaCl}$, and $\ce{Al2O3}$; which one has a higher melting point and why?
I have learned the following inter molecular forces, however the question the chapter is in ...
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Why does branching decrease density and melting point?
The general explanation given is that the chains are further apart, so the intermolecular forces are less, and as they are further apart, they occupy more volume, and the density is lesser. But the ...
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How does cross-linking between polymer chains increase the melting point of the polymer?
https://i.sstatic.net/uUcQr.jpg
Suppose we have this polymer chain. Now, we cross link some chains ( not all ) , so some chains get linked, and others remain as they are. What we now have is a '...
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Why is the melting point of KBr higher than that of CsCl?
I thought that when compounds have similar forces and charges, the one with the higher molecular weight has the higher melting point. If that is true, then why is the melting point of $\ce{KBr}$ ...
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When SiO2 changes state, what forces/bonds are being overcome/broken?
When silicon dioxide changes state, are the covalent bonds being broken (ie. the intramolecular forces) or is it the intermolecular forces?
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Why isn't the melting point of H2O very high, if the intermolecular forces are strong?
H2O has very strong intermolecular forces due to the hydrogen bonds that a formed within the compound. Usually this would mean the compound has a very high melting point as a large amount of heat ...
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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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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, $\ce{...
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Melting and boiling points of benzene and fluorobenzene
This species is a derivative of benzene, with a single fluorine atom
attached. Its melting point is -44 °C, which is lower than that of
benzene, indicative of the remarkable effect of fluorination ...
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How to calculate which ionic compound has the highest melting point?
Which of the following compounds has the highest melting point: $\ce{PCl5}$, $\ce{H2O}$, $\ce{NaCl}$, $\ce{SrCl2}$, $\ce{CaF2}$?
In general, ionic compounds will have higher boiling points than those ...
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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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