This is the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases (solid or liquid) at a given temperature in a closed system.

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Raoult's Law and Mole Fraction

Raoult's Law states that the partial vapor pressure of each component of an ideal mixture of liquids is equal to the vapor pressure of the pure component multiplied by its mole fraction in the ...
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Rocket propellants: accuracy of vapor pressure estimation techniques

I would like to determine the vapore pressures of a couple of substances (rocket propellants) over a significant temperature range within a ~10% error margin. For a first test, I tried to ...
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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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Is menthol an especially volatile molecule?

I have been studying a bit about odors and plant essential oils. Several sources claim that the fragrant terpenes found in these oils, such as menthol, eugenol, limonene, linalool, etc. are volatile ...
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Why does melting point depend on external pressure?

The melting point of a substance is the temperature at which the solid form's vapor pressure equals the liquid form's vapor pressure. I read that the vapor pressure of something depends ONLY on the ...
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84 views

How to calculate the total pressure in this question?

Here is the question: A container at $78\ \mathrm{^\circ C}$ initially contains $\ce{AB(g)}$ in equilibrium with $\ce{AB(l)}$: $$\ce{AB(l) -> AB(g)}$$ A catalyst (of negligible ...
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151 views

What is the mass fraction of C2HCl3 in the liquid phase?

Vapour-liquid equilibrium of a two-component ideal solution of trichloroethene (C2HCl3) and trichloromethane (CHCl3) is established at 25 °C. The mole fraction of CHCl3 in the vapour phase is 1. What ...
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Mass of sugar that was added to the water (Raoult's law)

Water has a vapour pressure of $15.5~\mathrm{mmHg}$ at $25~\mathrm{^\circ C}$. An unknown amount of the non-volatile sugar glucose ($\ce{C6H12O6}$) is added to $1.31~\mathrm{kg}$ of water and the ...
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Calculate the mole fraction of component B in this solution? (partial pressures)

The vapour pressure of a pure liquid solvent A is 0.80atm. When a non volatile substance B is dissolved in teh solvent, its vapour pressure drops to 0.60 atm. Calculate the mole fraction of component ...
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43 views

Does storing a hygroscopic reagent in a bottle makes it prone to absorb humidity from the air trapped inside?

I've got a full bottle of 99,5% acetone, which I'd really like to keep it as dry as possible, though without using molecular sieves or other dessicants. Once I open the bottle for the first time, use ...
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How does the phase change depending on vapor pressure and input partial pressure difference?

I have seen that when working with gallium at high temperatures (i.e. $600\mathrm{~^\circ C}$) a difference in phases is observed when the input partial pressure is changed (The vapor pressure at ...
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Is every substance in equilibrium with its vapours?

In one of my previous questions (How are odor and electronic structure related to aromaticity?), I got an answer from Jan: The smell of a compound as we perceive it usually depends on which ...
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A question about vapor pressure and boiling point

Question 1: If we have an open container which has water in it and is heated. If there is no lid over the container then how can this water ever boil as there will be no vapor pressure created over ...
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Get the molar fraction given the vapor pressure of a dissolution

If a dissolution has a vapor pressure of $24.4\rm{torr}$ and the vapor pressure of the pure dissolvent is $25.5\rm{mmHg}$, what is the molar fraction of the solute? Well, I just have to solve ...
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166 views

Minimum amount of water in pressure cooker

When cooking I would like to know the minimum amount of water I can add to my 6.2 L pressure cooker, worst case, so without any food. At second ring cooking the pressure is 0.8 bar. I assume I need ...
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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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116 views

Total pressure in a chamber calculation

I have a chamber containing two different gases and a liquid which needs to be heated at a certain temperature to bring it to vapor state. I have worked out that we can calculate the total pressure ...
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Relating 'temperature' difference to 'vapour pressure'

I am aware of the fact that with the increase in temperature, the number of molecules with more kinetic energy increases and thus, the vapour pressure increases. When we increase the temperature ...
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Relationship between vapour pressure and saturated vapour pressure

I need clarity on saturated vapour pressure in a closed system at equilibrium. How does saturated vapour pressure relate to vapour pressure?
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What happens when heating water in a pressure vessel?

Suppose that I take a pressure vessel that can withstand up to 2000 PSI. Now I fill it with water (not completely, but around 90%) and start to heat it with a direct flame. What I want to know is, ...
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189 views

Using vapor mole fraction and pressure to determine liquid mole fraction

I am studying Chemistry by Zumdahl and Zumdahl (9th edition) and I have come across a question in Chapter 11 that I can't figure out the explanation for: Liquid A has vapor pressure x , and liquid B ...
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Is dew and water vapour the same?

Is it possible to say water vapour and dew is the same? I know that the water vapour is the gaseous phase of water. But what is the dew? I just wonder how can I categorised it. Is it the liquid or ...
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what is the relation between partial pressure and vapour pressure? [duplicate]

I've read about Raoult's Law, and Henry's Law. So I wanted to know whether there is any relation between partial pressure and vapour pressure? As partial pressure is directly proportional to the mole ...
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The effect of air pressure on the “melting point”?

a) No effect b) The melting point increases when the air pressure increases c) The melting point decreases When the air pressure increases The boiling point has inverse relation with ...
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Unable to comprehend graph of aqueous lithium bromide vapour pressure

$\ce{LiBr}$ $Vp$ chart: http://www.mediafire.com/view/x77zc8wj11gthsj/LiBr_Vp.jpg or http://www.mediafire.com/view/u4dnocvbsf3atmu/Useful_Chart_LiBr.pdf Lecture in question (p.13) ...
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How does composition of air affect vapor saturation limit?

Suppose we hold temperature, pressure, and gas composition (say, a standard atmosphere) constant. Then we know that if we allow the water content of the air to vary it can range between 0 and some ...
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How can I turn natural gas from liquid to gas?

I hope I am not too off topic. I couldn't find a more suitable stack-exchange site for this, so if there is a better one, please point me to it. My question is the following: I am working on a ...
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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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How to calculate the equilibrium vapor pressure of a mixture of two substances?

The vapor pressure of a substance $\ce{A}$ is $20~\mathrm{torr}$. The vapor pressure of substance $\ce{B}$ is $40~\mathrm{torr}$. After pouring 20 moles of $\ce{A}$ into a container of 20 moles of ...
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Finding Kp at another temp with /\Hrxn [closed]

Took a pic of the paper I tried it on it on, has the exact problem description written at top, and what I tried. Figured that would be easier then typing all that. The answer is supposed to be 2.0.
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Applying Raoult's Law to a condensed gas mixture

So, here's the question which I'm having trouble solving : Suppose that we condense a gas mixture. At 25 celsius, what will be the pressure of benzene and of toluene over the obtained liquid. We ...
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How are pressure vessels heated?

I'm working on a project in which I'll be dealing with pressure vessels. As of now I've drawn/conceptualized everything on theory basis. The diagrams are made on the basis of theory, but then I came ...
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Pressure over a solution

I was wondering something, if I have the same molar fraction for two different substances for a vapor on top of a solution, will this mean that the pressure of each individual substance will be the ...
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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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How to calculate the vapor pressure of water?

$48~\mathrm{l}$ of dry $\ce{N2}$ passes through $36~\mathrm{g}$ $\ce{H2O}$ at $300~\mathrm{K}$, and this results in a water loss of $1.20~\mathrm{g}$. The vapor pressure of water is? The solution ...
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Is atmospheric pressure acting only on the contents or also on the container?

$22~\mathrm{g}$ of dry ice is placed in an an empty $600~\mathrm{ml}$ closed vessel at $298~\mathrm{K}$. Find the final pressure inside the vessel, if all $\ce{CO2}$ gets evaporated? Now by ...
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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 causes the lowering of vapour pressure in volatile/nonvolatile solvent mixtures?

"Based on Figure 13.18, you might think that the reason volatile solvent molecules in a solution are less likely to escape to the gas phase, compared to the pure solvent, is that the solute molecules ...
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How does grease become airborne?

When cooking in the kitchen you usually use some oil or butter to bake your meat and potatoes in. After some weeks without cleaning (which happens every now and then) the surroundings of the stove ...
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Can you concentrate alcohol by evaporating the aqueous solution at room temp and collecting on a cold surface?

I have a bowl containing cheap wine and an immersible fish tank heater. The heater warms the wine to 30 deg C. The bowl is located in a large closed bucket, where it sits on a support. The bucket is ...
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Understanding Millimeter of Mercury

A Millimeter of Mercury(mmHg) is by definition the pressure exerted on a column of mercury 1 mm in height. I found this definition confusing because it doesn't say how the diameter of the container ...
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How does Ostwald-Walker method work?

From searching online I found this: The apparatus consists of two sets of bulbs. The first set of three bulbs is filled with solution to half of their capacity and second set of another three ...
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Volatile and non-volatile solutes in solution

What's the difference between having a volatile versus a non-volatile solute at the boiling point of the solution? I've been getting mixed answers online concerning the differences of these two. This ...
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is sublimation a property of all substances?

I wonder if sublimation can be done only on certain substances like Iodine or it can be done on all substances in other words, can sublimation be done for example on water? if it can not then why?
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How to calculate melting/boiling points at different pressures

I know water boils at below room temperature in a vacuum, and want to know if there's an equation to calculate the melting or boiling points of elements or compounds at a given pressure. How would I ...
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Liquefying butane in a freezer

If place a can of pressurized liquid butane (such as a lighter refill canister) into a freezer to get it below its boiling point of $-1\ \mathrm{^\circ C}$, and then release it into a container kept ...
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Clarification on vapor pressure

If I have a glass of water, and the vapor pressure is the point of equilibrium where the liquid molecules are becoming gases and the gas molecules are colliding and becoming liquid at the same rate, ...
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Condition for formation of azeotropes

Consider a binary azeotropic solution of two volatile components $A, B$. I wanted to try and find out the required concentrations of $A, B$ in the solution in terms of their vapour pressures. I tried ...
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Which of these solution have the lowest vapor pressure in 298 K?

Which of these solution have the lowest vapor pressure in 298 K? Please give a brief explanation. 0.01 m $\ce {CaCl2}$ 0.01 m $\ce {NaCl}$ 0.02 m $\ce {NaCl}$ 0.015 m $\ce {CaCl2}$ 0.01 m $\ce ...