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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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 ...
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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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82 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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46 views

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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58 views

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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104 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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114 views

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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157 views

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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227 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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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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101 views

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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1answer
59 views

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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459 views

What is the reason for this azeotrope formation?

What is the reason for the formation of an azeotrope? I mean why with certain compositions, one component alone cannot go to vapour phase. Is there any extra force holding the two components together? ...
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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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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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93 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 $100\ \mathrm{^\circ C}$ will be transferred as well. Does the usual tap water ...
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484 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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60 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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3answers
146 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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60 views

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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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 ...
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396 views

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 ...