Questions tagged [inert-gases]

Gases which do not undergo chemical reactions (except the loss of electrons to become ionized).

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Interpretation of change in entropy and how to formulate an expression for how much energy required to mix gases.?

From statistical mechanics one cab derive the change of entropy of the mixing of two ideal gases with the result $$\Delta S_\text{mix} = - n R \Sigma_{i} x_i \ln(x_i)$$ where $n$ is the total amount ...
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Physical reason for Helium-hole?

I just found a "Helium-hole" from atmospheric data provided here. I was actually looking for this, and the first search was immediately succesful, a hole was found from; Time: 05.01.2002, 05:00 UTC ...
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Why completing an octet stabilises an atom, quantum mechanically? [duplicate]

They say that Neon $Ne$ is stable because it has 10 electrons and with 10 electrons it completes its octet and completing an octet decreases the potential energy of an atom to the minimum and a system ...
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Can mercury escape undectectably from a CFL bulb? or does it have to shatter for the mercury to be liberated? [closed]

I read that the mercury vapour inside a fluorescent lamp is pressurized at 0.2% of atmospheric pressure. Can mercury escape undectably through a small crack in the glass yet still light up? Or will ...
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At what pressure does the helium undergo phase transition at room temperature?

At what pressure does the helium undergo phase transition at room temperature? I can not find phase diagram at room temperature.
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Plasma generated with gas and how far does it penetrate the skin

I know Far Infrared can penetrate the body’s tissues 1.5 inches (almost 4 cm) beneath the skin. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3699878/ But how far will a plasma field generated with ...
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397 views

Calculating heat absorbed from expanding gas [closed]

I'm trying to calculate the amount of heat absorbed per kg of different types of gas, namely compressed air and carbon dioxide. Starting with carbon dioxide, I found that the Joule-Thompson ...
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Understanding why 2*density of a isolated gas equals half the initial temperature

A vertical cylinder of cross-sectional area 0.050 m2 is fitted with a tight-fitting, frictionless piston of mass 5.00 kg. The cylinder contains 3.00 mol of an ideal gas at 227°C. At what temperature ...
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240 views

Gauge Pressure and Bar Pressure [closed]

I ran into a problem trying to calculate the absolute pressure of an isolated system. I was given that the gauge pressure in a tire is 200kPa or 2 bars. To get the absolute pressure I would have to ...
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Calculate pressure from partition function with separated volume geometric parameters?

How does one calculate the pressure from the partition function if it is specified in terms of three parameters defining the space of which the gas occupies, but all three parameters are not always ...
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Recombination time for ionized atoms in a low pressure gas?

I am looking into some new physics and had the following question come up: You have a neutral gas of let's say, CO atoms at 1 nanoTorr. An electron(s) comes passing through the gas ionizing only 1% ...
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Where I can find information about how helium gas diffuses through different polymer materials

I need more experimental information about helium gas diffusion in solid materials such as different plastics, metals, ceramics etc. For example I am scientifically curious about what is the polymer ...
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How to measure the atomic radius of a noble gas?

How exactly can you measure the atomic radius of a noble gas such as Neon or Helium accurately? Would liquefaction help? I heard that noble gases are the only common elements which have not been ...
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Can any gas be liquidified by lowering the temperature?

Can any gas be liquidified by lowering the temperature? What happens with gases at absolute zero? Are there gases that remain gases at absolute zero? Do their molecules move at these temperatures? ...
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Why do noble gases stabilize plasma discharges?

In the plasma literature, noble gases—usually helium or argon—are frequently said to 'stabilize' plasmas. For instance in this patent, the inventor states that the plasma can be stabilized "by adding ...
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Why do real gases deviate from ideal behavior above the Boyle temperature?

My textbook says that Boyle temperature is the temperature at which a real gas shows maximum ideal gas behavior. Below the Boyle temperature, molecules come too close and intermolecular forces skew ...
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Potential vs Kinetic Energy of Particles in Gas

"In the gas phase, the molecules are freely moving particles traveling through space, where the kinetic energy associated with each particle is greater than the potential energy of intermolecular ...
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How to derive the two-term approximation for the Boltzmann equation?

Starting with the Boltzmann equation in terms of $f(t,\vec v,\vec x)$ or $f(t,\vec v)$ http://en.wikipedia.org/wiki/Boltzmann_equation $$\left(\frac{\partial}{\partial t} + \vec{v} \, \...
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Could I use an electron gun to make plasma?

Could I ionize a gas using an electron gun and knock off electrons in the gas to make plasma?
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197 views

Can we create a force shield using a gas that acts like a non-Newtonian fluid?

Most people know that if you mix cornflour with water it creates a liquid that if a force is acted upon it it solidify for an instant then returns to a liquid state. will we be able to create a gas ...
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Zeolite-based oxygen concentrators

I wonder, what is content of output of zeolite-based pressure swing adsorption oxygen concentrators (both oxygen output, and exhaust output)? Yes, they can produce 95% oxygen. But what's the ...
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Calculating laser wavelength/power to cause emission of light in a gas?

I've become interested in volumetric displays. In particular I'm looking at a pair of lasers scanning a volume of gas such that the intersection of the lasers would supply enough energy to cause the ...
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Gas Cylinder Life

Say I have a gas cylinder filled with nitrogen to some volume at some pressure. On that cylinder I have a regulator so that I get a steady pressure out. I wish to discharge the cylinder. How many ...
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Why are noble gases used for lights?

I know that neon is used in advert signs due to its inertness. However, I am not entirely sure how the inertness is exploited. I think it is because Ne being inert means that after electricity frees ...
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Neon lamp: minimal breakdown voltage

I am looking at this formula from wiki for breakdown voltage in gas discharge lamps, and I see its linear by length (d) (oops, I see it's divided by $ln$) $$\frac{Bpd}{\mathrm{ln}\ Apd-\mathrm{ln}\ (...
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467 views

How 'pure' is liquid nitrogen?

I've been doing an experiment using liquid nitrogen, and am aware that pouring it into different containers gives a chance for other gases to liquify and contaminate it; what's a good estimate for the ...
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If you put a latex balloon in a vacuum, how much would it expand?

If you put a latex balloon in a vacuum, how much would it expand? And would it pop? Assume it doesn't leak. EDIT: Some numbers: Ambient pressure is 100 KPa, balloon is perfectly spherical with a ...
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902 views

How were noble gases discovered?

Noble gases are chemically neutral. They don't react with anything. So, how were they discovered?