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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Boiling point and melting point of dihalobenzene compounds [duplicate]

In Dichlorobenzene what explains the boiling and melting point of the 3 structures that can be formed? According to Google The melting point decreases in the order- Para>Ortho>Meta And Boiling ...
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Alkane, Alkene, Alkyne boiling point

I'll be having a national test tomorrow. I'd like to clarify so that I don't answered it wrong. Question: Which of the following has higher boiling points? Alkanes, Alkenes, or Alkynes? And why? ...
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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 ...
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How can I calculate the boiling temperature of a pure substance as a function of pressure?

I want to make an algorithm that will give me the boiling temperature of a substance as a function of pressure, the critical temperature of a substance, and the critical pressure of a substance. I ...
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389 views

Boiling and melting point of trans- and cis-but-2-ene

The boiling point of trans-but-2-ene is lower than that of its cis isomer but the melting point of the former is higher than the later. Why is it not following the same order? Is there any factor of ...
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Does the boiling boint of miscible liquids follow a linear relationship?

I want to create a steam bath for a reaction the proceeds well at 105℃. I cannot use pure (demineralized, anyway) water for this, since it would boil at 100℃ at STP. As such I figured ...
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Why does decreasing the pressure of the system increase the relative volatility of a binary solution?

In our teaching lab, we were posed with the following question as an exersize: If the boiling points of two compounds differ by 50 degrees C at atmospheric pressure, what will be the effect on the ...
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42 views

Comparing the strength of metallic bonds

Why is the boiling point of iron higher than magnesium?
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The relationship between energy and air pressure?

When boiling water at room temperature, what is the relationship energy has with the air pressure that is making the water boil cold instead of hot?
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Effect of inductive effect on boiling point,melting point and dipole movement

In my book the following was written:- Inductive effect is a permanent effect operating in the ground state of the organic molecules and hence is responsible for higher melting point, boiling ...
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40 views

How to purify water with activated carbon?

If I am not mistaken, distilling water does not remove all possible impurities. Chemicals with boiling points less than $100 ° C$ will be transferred as well. Does the usual tap water contain such (I ...
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73 views

Effect of a solute on the boiling point of the solution

I have a question regarding the boiling point. If we have two different aqueous solutions, let's say one with glucose and the other with ethanol; and, Both solutions have same molarity 1M. Do they ...
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37 views

Calculating boiling point of a solution

What is the boiling point of an aqueous solution that has a vapor pressure of $23.0~\text{torr}$ at $25~^\circ\text{C}$? $(P^\circ_{\ce{H2O}}=23.78~\text{torr};~K_b= 0.512~^\circ\text{C/m})$ To ...
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What determines humidity limit / dew point of the air? - Why can air only hold a certain amount of water?

From Wikipedia: The dew point is the temperature at which the water vapor in a sample of air at constant barometric pressure condenses into liquid water at the same rate at which it evaporates. At ...
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85 views

Is this the right conclusion for a thought experiment?

In this thought experiment, let’s consider the surrounding to be air that is composed of entirely water vapor (no other species like $\ce{O2}$ and $\ce{N2}$ are present). The surrounding is infinitely ...
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Will the water at the bottom of the tube boil at the same temperature as the water at the top of the tube?

Consider a long, vertical tube of water, as shown below: Where $P_\mathrm{atm}$ is the atmospheric pressure and $P_\mathrm{bottom}$ is the pressure at the bottom of the tube. The tube is long ...
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What are the physical properties affected in ZnO when there is a sulfur impurity?

I have a question. I work at a brass metal foundry where one of our waste products is $\ce{ZnO}$, which we sell. Because we have been making new alloys which contain sulfur, our $\ce{ZnO}$ has a very ...
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Experiment to prove that water has air

In elementary school, there was an experiment to show that water has dissolved air, which involved boiling some water and observing the drops at the surface of the container, and this proved that ...
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Boil to dry 50 litres water

I would like to find out how long it would take to completely turn 50 litres of water to steam. Let's assume power of 2500 W and the water is already at boil. I am not very scientific so please ...
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Does more branching lead to lower boiling point in alkanes?

List the following alkanes in order of increasing boiling point. A. $\ce{CH3(CH2)4CH3}$ B. $\ce{(CH3)2CHCH(CH3)2}$ C. $\ce{CH3CH2CH(CH3)CH2CH3}$ Answer: $C<B<A$, low to high. ...
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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

Arrange these compounds: $\ce{CO2}$, $\ce{CH3OH}$, $\ce{RbF}$, $\ce{CH3Br}$ in order of increasing boiling points. I think I should consider the forces between them, that is: $\ce{CO2}$: ...
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711 views

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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941 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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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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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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Melting points and boiling points of primary alcohols do not follow the same trend

If one considers boiling points (in °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 Van der Waals ...
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Why are the boiling points of aldehydes less than those of ketones?

Both aldehydes and ketones have a carbonyl group, but since the carbonyl group of ketone is between alkyl groups, wouldn't it be more difficult for it to form hydrogen bonds than aldehydes? Whey then, ...
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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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261 views

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 [closed]

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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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 ...