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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Why is the boiling point of alkyl iodide is more than alkyl fluoride?

As far as I know, more the polar character of the organic compound, more will be the energy required to break the bond and thus more boiling temperature. Here in this case, $\ce{R-F}$ is more polar in ...
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Why is the boiling point of a solution higher than that of a pure solvent? [duplicate]

My reasoning When non-volatile solid solute is added to a solvent some of the liquid solvent molecules are replaced by solute molecules at the surface.The lesser the number of solvent molecules at ...
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Boiling point of: Halogenoalkanes vs alkanes vs alcohols

We know that $\textbf{Boiling point} (\text{alcohol})>\textbf{Boiling point} (\text{halogenoalkane})>\textbf{Boiling point}(\text{alkane})$ with same number of $C$ atoms, but is the following, ...
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Melting and boiling point trend in Group II

The following picture shows the melting and boiling point trends down group II elements. I have added question marks where the variability in data was rather disturbing (over two hundred degrees ...
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Vapor pressure, volume and boling point

The saturated vapor pressure is designated as the gas pressure in a closed container when the evaporation process has reached an equilibrium (when there are as many molecules returning to the liquid ...
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Is this Boiling point apparatus?

I have some chemistry equipment but I am not sure what it is for; I think it may be apparatus for measuring elevated boiling points. I have included a drawing of how I think it should go together. ...
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Heating of mixture of gases with one gas barely above its boiling point

What happens when mixture of two gases is heated in a closed container? If one gas expands faster than the other and increases pressure of the container enough so that the boiling point of the other ...
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Why is the boiling point of rectified spirit lower than alcohol absolute?

The boiling point of rectified spirit is ($78.1~\mathrm{^\circ C}$) while that of absolute alcohol is ($78.3~\mathrm{^\circ C}$). I know its too small, but shouldn't the addition of impurities ...
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31 views

How to separate benzyl alcohol and meta-cresol

Benzyl alcohol and meta-cresol boiling point's are not so different, the fractional distillation will be very difficult, what can i do for separate this two composites ?
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Dissociation of H3PO4 and colligative properties

Which of the following solutions that have concentrations of $0.01\ \mathrm{M}$ show the highest elevation in boiling point and why? A) $\ce{NaCl}$ B) $\ce{CaCl2}$ C) $\ce{H3PO4 }$ D) $\ce{...
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Why do alcohols and ethers have approximately the same solubility in water but different boiling points?

In Morrison & Boyd, I found this question: Butan-1-ol (b.p. $118~\mathrm{^\circ C}$) has a much higher boiling point than its isomer diethyl ether (b.p. $35~\mathrm{^\circ C}$), yet both ...
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High boiling point of ionic compounds [duplicate]

An ionic compound has an giant ionic lattice with strong electrostatic forces of attraction between the positively-charged cation and the negatively-charged anion. These ionic bonds are very strong ...
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132 views

Elevated boiling points in alkanes with even number of carbons [duplicate]

Why do alkanes with even number of carbon atoms have greater boiling points than those with odd number of carbon atoms?
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Does a freezing point of a substance always increase as its boiling point increases?

I am studying for an introductory to physical sciences test and came upon a chart describing substances found in petroleum and the distillation process. Each freezing point increases as each boiling ...
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How to determine what organic molecule has the highest boiling point?

Compare and answer which one has the highest boiling point: $\ce{CH3CH2CH2CH3}$ (butane) ... [−1 to 1 °C; 30 to 34 °F; 272 to 274 K] $\ce{CH3NH2}$ (methylamine) ... [−6.6 to −6.0 °C; 20.0 to ...
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Colligative properties

I have some problems with these properties. 1) Lowering vapor pressure and boiling point. It happens because the solute molecules take space in the surface of the liquid so a lower number of the ...
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Why boiling point of Sulfuric acid is much higher than that of phosphoric acid?

Why boiling point of sulfuric acid is much higher than that of phosphoric acid? According to the data book , • The boiling point of Sulphuric sulfuric acid is 337 °C (639 °F; 610 K) When ...
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55 views

Boiling and Exploding Beaker?

A few days ago, I was creating a solution which involved boiling water. I had two 4L beakers on identical hot plates. After around 10 minutes, the first one boiled. Waiting another 30 minutes, the ...
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180 views

Boiling point and vapor pressure

Does a liquid having higher vapor pressure have a lower boiling point? I think so because I read in wikipedia that, "A substance with a high vapor pressure at normal temperatures is often referred to ...
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percent dissociation

Would these answers be correct? . Of 100% of the NaCL molecules dissociated, the Van't Hoff factor i, would be equal to 2 for NaCl. We assumed it equaled two when we figured out Kb of the NaCl ...
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Strength of London Dispersion Forces - Why do rings have stronger dispersion forces? [duplicate]

My textbook says, Rings can be stacked on top of one another to give rise to stack of closely spaced rings, hence they have overall stronger dispersion forces. Ring > Linear > Branched With similar ...
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336 views

What is the boiling point and density of LSD?

I have tried to do a lot of research and didn't succeed to find the boiling point and density of LSD. I would want to know this information. In addition, I can't use Clausius–Clapeyron equation ...
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What is the temperature at which lava evaporates?

According to this article -> http://ntrs.nasa.gov/search.jsp?R=19660041998 Lava evaporates under natural conditions, but apparently, only a little bit. I'd like to know the temperature at which ...
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Boiling points on bond strength

It is common to find in Chemistry texts that certain groups of compounds have lesser boiling points. The main given reason is that the bonds formed btw the atoms are weaker. For eg: The relation btw ...
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Why does CO2 have higher boiling point than CO?

The intermolecular forces between $\ce{CO2}$ molecules are dispersion forces, while the forces between $\ce{CO}$ molecules are mostly dipole-dipole attraction forces. So, why does $\ce{CO2}$ have a ...
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Why does chlorine have a higher boiling point than hydrogen chloride?

Chlorine has a boiling point of $238~\mathrm{K}$ while hydrogen chloride has a boiling point of $188~\mathrm{K}$. Hydrogen chloride has dipole-dipole forces so I would expect it to have greater inter-...
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Trend in the boiling point of the hydrogen halides

The boiling points of the hydrogen halides are as follows: $$\begin{array}{cc} \hline \text{Species} & \text{Boiling point / }\mathrm{^\circ C} \\ \hline \ce{HCl} & -85.1 \\ \ce{HBr} & -...
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Why do chlorinated silanes have lower boiling points than their methane analogs?

The boiling points of the chlorinated silanes and methanes are given below: $$\begin{array}{ccc} \hline \text{Species} & \text{Boiling point (X = Si) / }\mathrm{^\circ C} & \text{Boiling ...
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286 views

Why is the boiling point of CH3COOH higher than that of C2H5OH?

Why is the boiling point of $\ce{CH3COOH}$ higher than that of $\ce{C2H5OH}$ ? Both are polar molecules held by hydrogen bond.
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Why does the boiling and melting point decrease as you go down group 1 and vice versa for group 7?

I used to think that because an alkali metal needs to lose one electron to complete its outer shell, when the atom increases in size (atomic radius), the electron would be easier to lose as the ...
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boiling point and distillation relation

i need help with the fractional distillation method of a couple of substances at least more than two substances , just like air actually what am i looking for is that why do substances in air with a ...
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At what temperature (in kelvin) are most of the elements on the periodic table liquids?

This question is out of pure curiosity. At what temperature are a majority of the elements on the periodic table in a liquid state/phase of matter? For the purpose of this question, assume the ...
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How are the boiling points of Tungsten and other metals determined and proved?

The boiling point of Tungsten is 10,030 degrees Fahrenheit. How was this determined and proved? And more generally how are the boiling points of metals determined and proved? Is it really so simple ...
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What is the connection between vapor pressure and intermolecular force explanations of boiling?

I've had boiling explained to me in two ways, and I'm having trouble understanding how they connect. The first way is that a liquid is held together by the intermolecular forces, and boiling involves ...
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Why do the melting points of Group 15 elements increase upto Arsenic but then decrease upto Bismuth?

The boiling points of group 15 elements increase on going down the group (or, as size increases) but the same is not true for the melting points. The melting points increase from $\ce{N}$ to $\ce{As}$ ...
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What [if anything] is special about the boiling process of purifying water (excluding temperature)?

I know that water boils at $100~^{\circ}\rm C$. I also know that the standard way to purify water is to boil it for roughly a minute. What I'm curious about is, what properties of the boiling process ...
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Order of Boiling Points for Group 15 Compounds

What is the order of boiling points of the following $\ce{NH3}$, $\ce{PH3}$, $\ce{AsH3}$, $\ce{SbH3}$ and $\ce{BiH3}$ . What I thought was, that as H2O has a higher boiling point compared to its ...
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How can you boil milk without causing it to foam and overflow?

I have looked at this Why does milk overflow... But I've not found a solution to prevent the milk overflowing. I remember reading (cannot recall the source) that in industries where milk is boiled a ...
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202 views

Why does butanoic acid have a higher boiling point than isobutyric acid?

Why does butanoic acid have a higher boiling point then isobutyric acid, when they have similar molar mass and molecular structure? Butanoic acid ($\ce{C4H8O2}$) has a molar mass of 88.11 g/mol, ...
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How to calculate the boiling point of a solid substance?

Say that I have a solid substance; I know its density, mass, volume, melting point, specific heat, the pressure which it is under, and nothing else. (for now.) How do I find the heat at which it ...
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Why does cooking oil lower the vapor pressure of water?

I added different amounts of oil to different containers with 50mL of water and weighted the containers. Then I heated the containers for 15 minutes in a water bath and weighted again. I noticed that ...
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Why there is an exception in melting and boiling point in p block?

Why is the boiling point and melting point of 15th group and 16th group has an exception? As we know that as molecular mass increases boiling point and melting point will also increase. So on going ...
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Justification for Freezing Point Depression & Boiling Point Elevation in Solutions?

I was wondering if the following justification for freezing point depression and boiling point elevation are conceptually correct. The reason why I ask this question is because I have been self ...
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Why do ionic compounds have higher melting and boiling points despite having smaller radii?

Why do ionic compounds have higher melting and boiling points despite having smaller radii? I thought that the closer the two ions are, the larger the repulsive force, and therefore it should rather ...
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1answer
371 views

Boiling/melting points of cyclohexane and cycloheptane

I’m looking at a chart in my book, and while cycloheptane has a higher boiling point than cyclohexane like I’d expect, cycloheptane has a melting point of −12 °C, while cyclohexane has a melting point ...
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Which substance has the highest temperature range between melting and boiling point

Which substances exist that are normally liquid and that will not freeze nor boil even at relatively low/high temperatures as compared to the freezing and boiling points of water? Or how can I ...
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How is it possible for a substance to have a high heat of vaporization but a low boiling point?

The final paragraph of Dissenter's question here is worthy of standing alone: [H]ow does one square a high heat of vaporization with a low boiling point? If it takes a lot of energy to vaporize ...
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Why do cyclic hydrocarbons have higher boiling points than their acyclic isomers?

As pointed out in the comments to this question, cyclic hydrocarbons have higher boiling points than their acyclic isomers. The major attractive force for hydrocarbons should be the London forces, ...
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Why do cyclic ethers have higher boiling points than their acyclic isomers?

TL;DR version is the question title. Some context and data follow. I was creating an assignment for my organic chemistry students in which they would need to draw as many isomers as they could from a ...
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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? ...