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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Does more branching lead to lower boiling point in alkanes?

Why is it that B has not a lower boiling point than C? Is it not more branched? I believe branching decreases surface area, leading to less intermolecular interactions, and to a higher bp.
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Factors of London Forces

In class we learnt that the London forces become stronger as the relative molecular mass increases. Not just as in organic chemistry but in things like the halogens. However, as I understand, the ...
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How to determine the composition for a sucrose/ zinc nitrate solution from its freezing point?

A $4~\mathrm{g}$ mixture of sucrose ($\ce{C12H22O11}$) and zinc nitrate ($\ce{Zn(NO3)2}$) is dissolved in $150~\mathrm{g}$ of water. If the resulting solution freezes at $-0.768~^\circ\mathrm{C}$, ...
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Why does tomato soup “explode” when boiled?

When you boil tomato soup it very easily "explodes" when reaching the boiling point. Why is that? A related question has been answered here before: Why do some solutions eventually stop boiling and ...
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arrange these compounds: CO2, CH3OH, RbF , CH3Br in order of increasing boiling points

I think I should consider the forces berween them that is: CO2: dispersion forces RbF: dispersion and ionic forces ch3oh: Dipole-dipole interactions, Hydrogen bonding and disperaio forces ...
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Liquefying butane in a freezer

If I were to put a can of liquid butane which is under pressure (eg. Lighter refill) in a freezer to get it below its boiling point of $-1^\circ C$, If it were released in an also frozen container ...
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Why doesn't the boiling point of an aqueous solution depend on intermolecular attraction?

I understand that boiling point is a colligative property for aqueous solutions, and that it empirically depends on the mole fraction of the solute, rather than the identity of the solute. I ...
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Boilng vodka for A/C cleaning

I hope this doesn't sound too strange. I have plenty of cheap vodka and want to clean the A/C on my car. So I thought about boiling 1/2 litre of vodka in my car while I ran the A/C with ...
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Why do the melting and boiling points of the noble gases increase when the atomic number increases?

Can anyone explain why the melting and boiling points of the noble gases increase as you go down the periodic table? Edit: What causes the melting and boiling points to rise when the atomic number ...
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1answer
482 views

Why Tetrachloromethane has a higher boiling point than Trichloromethane?

London Dispersion Forces are present in all either polar or non polar molecules. Molecules also exhibiting Dipole-Dipole Interactions (in addition to the LDP) must have stronger forces of attraction ...
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Why Isodecane (B.P.: 327 *C) has a higher boiling point than decane (B.P.: 174.1 *C)?

Branched chain molecules have lower boiling point than straight chain molecules because branched chain molecules have a smaller surface area where they can be attracted by other molecules. Then, why ...
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Boiling point of a liquid increasing with temperature?

In my textbook, a statement is given, as follows: Boiling point of a liquid increases with increase in temperature However, I was wondering, isn't this wrong? The boiling point of a liquid ...
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Which factors best account for the increase in boiling point?

The boiling points of $\ce{CH3COCH3}$, $\ce{CH3COC2H5}$, and $\ce{CH3COC3H7}$ are $56˚C$, $80 ˚C$, and $102 ˚C$, respectively. What factor(s) best account(s) for this? I believe london ...
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Boiling-point elevation paradox

This is the boiling-point elevation equation: $$ \Delta\mathrm{T}_{b}=ib\mathrm{K}_{eb}. $$ If we do the limit of the above, for $b\rightarrow\infty$ we find that the boiling-point elevation is ...
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1answer
585 views

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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Comparision of boiling points

I was comparing boiling points of $CHCl_3$ and $CH_3Cl$. According to me B.P. of $CHCl_3$ should be higher due to it's higher molecular mass than $CH_3Cl$, but the answer is opposite ,ie. B.P. of ...
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1answer
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Smelly matters in urine - do they have lower or higher boiling point than water?

I don't know what exactly are the compounds that causes urine to be smelly, but does it (or do they) have higher or lower boiling points than water? If I have both liquid and exposed them to open air, ...
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Boiling point of Coca-Cola

Inspired in part by the question boiling point of vodka - given that the exact ingredients of Coca-Cola are kept secret, based on what is known, what would a viable prediction of the boiling point of ...
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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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1answer
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Melting points and boiling points of primary alcohols do not follow the same trend

If one considers boiling points ($^{o}C$) 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 Wan der Waals ...
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Why is the boiling point of aldehydes less than that of ketones?

Both have a carbonyl group. Since the carbonyl group of ketone is between alkyl groups it would be difficult for it to form hydrogen bonds compared to aldehydes.Then, aldehydes should have a higher ...
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Which among phenol and 1,2-dihydroxybenzene has the higher boiling point?

My attempt Based on symmetry: I think that looking for symmetry phenol has a higher boiling point than 1,2-dihydroxybenzene because the two -OH groups projecting out from the benzene ring of ...
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At what temperature will proteins and fats boil in a vacuum?

A question was asked on another stackexchange site: This is not nice perspective, but eventually it will happen. An astronaut falls out of spaceship because of damage caused by collision with ...
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Calculate Ethanol content after heating for N minutes

Does there exist a formula I can use to calculate alcohol content of a solution after heating it for some time? I have the following use-case: I am making a pecan pie. I have a thick sugary solution. ...
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Boiling point and solubility

Which one of the following compounds has the highest solubility : $$\ce{CH3CH3 \ \ \ \ \ \ \ \ \ CH3-O-CH3 \ \ \ \ \ \ \ \ \ CH3CHO \ \ \ \ \ \ \ \ \ CH3OH}$$ Which one of the following compounds ...
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Boiling and Melting point of Lithium (or any other element that does not occure in free state)

The melting and boiling point of Lithium as compared to other members of the Alkali group metals is high. But, Lithium does not occur in the free state. So, what does it mean that it has high ...
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1answer
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Why does the boiling and freezing-point of non-polar molecules rise with increasing molecular mass?

In the section about fuels, my textbook mentions that the boiling and freezing-points of alkanes (which are non-polar) increase with an increase in molecular mass due to London dispersion forces. ...
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Will gaseous ionic compounds be free moving ions?

I knew while learning about electrolysis that if the ionic compound is molten it becomes free moving ions. If that is the case, what will happen if I continued heating till it reaches the boiling ...
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Boiling point of vodka

What is the boiling point of vodka? I have found the boiling point of ethanol, ~173 (degrees) F. However, I am unable to find the boiling point of vodka. I found some information on it, but I do not ...
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Why do different substances have different boiling points?

For example, why does for example oxygen turn into gas at a much lower temperature than water? Does it have anything to do with the molecular structure? A water molecule does have a more complex ...