Gas Definition and 1000 Threads

Hi all, in this question i was asked to find the percentage change in the density, my approach was as following, first i find the change in volume due to putting the gas into the other vessel as: $$ P_{1}V_{1}=P_{2}V_{2}\;\; → \;\;V_{2}=\frac{P_{1}}{P_{2}}V_{1} $$ now i use $$...

To solve this problem I used two equations: $$ PV=nRT, $$ where ##P## is the pressure, ##V##the volume, ##R##the gas constant, ##T##for temperature and is##n##the number of moles, related to the mass ##m## and molar mass ##M## by $$ n=\frac{m}{M}. $$ It will be also necessary consider the...

Can someone please tell me where I am wrong, here goes the question: to a container filled with gas, U shaped pipe is attached, as shown in the picture(picture below). What is a gas pressure in the container if the height of the pillar of mercury in barometer is 740 mm? The way I solved it is...

Hi all, The idea is to generate as much as possible water steam from heat of internal combustion engine exhaust gas. The so called steam generation device is a simple sloped engine exhaust pipe where water from engine cooling and hot gas is fed at the top and all the mix is exiting at the...

(1) Incorrect, since the root mean square speed(c^2）is directly proportional to the temperature, but it will just affect the average kinetic energy, doubling the k.e., but not related to the potential energy. (2) Correct, since the volume of gas is directly proportional to the temperature (3)...

The answer given for part (c) in the back is that temperature doesn't change as the gas in cylinder A expands to fill cylinder B. The thermodynamic system here is composed of the two cylinders A and B joined by some pipe. But, I cannot find a satisfactory explanation for temperature...

There is no atmosphere pressure. My work : pA=k(x-x0) => pA=(k/A)(V-V0) But this should be false beccause I want to use W=∫PdV to find work done by the gas but my final anwer is wrong ... Please guide me where my mistake is if you have enough time. Thanks.

Homework Statement:: I am trying to understand a formula given in our book for determining molar heat capacity of an ideal gas under different thermodynamic processes using a single formula, but it is confusing. The exact formula for different processes is in the screenshots below. Can someone...

It is a 1D Tonk gas consisting of ##N## particles lined up on the interval ##L##. The particles themselves have the length ##a##. Between two particles there is a gap of length ##y_i##. ##L_f## is the free length, i.e. ##L_f=L-Na##. I have now received the following tip: Determine the...

I have a question about the temperature of HII gas. According to Table 1.3 in Draine's book (physics of the interstellar and intergalactic medium) this temperature is T~10^4 K. I get a similar value by using the Saha equation for a hydrogen gas. However, a naive estimate of the same temperature...

P1=1.9 and P2=4.8. Question: what is the total change in internal energy This is what I have so far but it is still incorrect I believe: U= (3/2)(1/2)(2.9)(1.01x10^3)(8x10^-3) Where am I going wrong?

Anyone outright experience or understand tips and tricks to apart/separate a rubber-ended hose with the gas regulator/connector (as the right pipe mouth below but sorry no rubber-end hose pic) ? It indeed so hard so any clear idea, with keep everything intact unbroken on mind, how to do and by...

Hi, I am not quite sure if I have understood the second task correctly, but I proceeded as follows. It's about what happens to the isothermal compressibility when the free energy becomes minimal. In the first task there was already the equation ##\kappa_T=\frac{1}{V}\Bigl( \frac{\partial^2...

Molecular speed of gas is generally $$v=\sqrt{\frac{3RT}{M}},$$where R is gas constant and M is molecular mass. Can we use this formula for the air as well, when the air is a mixture of different gasses?

For now it is only about the 1 task If the task states that: You can approximate that their dynamics in water resembles that of an ideal gas. Does it then mean that I can take glucose as the ideal gas and then simply calculate the entropy for the ideal gas?

For a freely expanding ideal gas(irreversible transformation), the change in entropy is the same as in a reversible transformation with the same initial and final states. I don't quite understand why this is true, since Clausius' theorm only has this corrolary when the two transformations are...

I was thinking the other day about green houses and how they would act in space or on another planet without an atmosphere. I know that green houses work on Earth by stopping convection but could they theoretically trap heat in a non atmospheric environment? I am imagining a material that allows...

Figures: Attempt at a Solution: $$L=0,015\, \textrm{m}\qquad R_2=0,01\, \textrm{m}$$ $$R_1-R_2=R_D=0,0075\, \textrm{m}$$ $$L=0,04$$ $$\rho_1=\dfrac{p_1}{R^2T_1}=\dfrac{p_1\bar{M}}{RT_1}=1,164\, \textrm{kg}/\textrm{m}^3$$ Calculate total volume ##V_A+V_B##: $$V_B=\pi \cdot R_2^2\cdot...

Hello, I just learned about the binding capacity of Hemoglobin (Hb) and that it is proportional to the partial pressure of O2 in the blood here is the curve : it does have a sigmoidal shape, but here is the problem: in the lecture, it's said that Hb has an increasing affinity to O2 the more...

The general balance equation is as follow: d[m{u+gz+v2/2)sys=(u+gz+v2/2)dmin-(u+gz+v2/2)dmout +dq+dw. I understand that I would take in consideration the cross sectional area as well as the mass flow rate. However I can't figure out what else to consider as if atm pressure should be considered...

For the first calculation of the velocity of the gas I use the first equation and this converted in meter would be look like this (first value as an example) v=299792458 m/s * (6.76813x10^-7-6.768x10^-7)/6.768x10^-7 =5836.03m/s or 0.0019c this was the velocity of the gas for the first spectral...

Hi, I've been thinking about the solution for cleaning a water-cooled gas cooler and would love to hear some advice from the smarter people with more experience. Description - I will try to roughly explain the concept. Gas Cooler is used to decrease exhaust gas temperature. The exhaust gas...

With a real inert gas (i.e. nitrogen N2) being compressed in a piston-like configuration, I'd like to estimate the peak pressure and peak temperature at the instant the gas is brought to full compression. Initial pressure and initial temperature (in the uncompressed state) are known: typically...

Hey all. I'm trying to understand the evolution of the velocity distribution function of a gas undergoing free expansion. I know that at t=0, the velocity distribution function is given by ##u(t=0, x)=Ax^{1/2}##, where ##A## is a known constant. From the momentum equation, I have: ##du/dt+u...

Hi, I recently read the following article on BBC online: "Revealed: Huge gas flaring emissions never reported (https://www.bbc.co.uk/news/science-environment-62917498)". Can they not use the ‘waste’ gas from flaring to generate electricity? Is it not feasible or economically viable? Do they...

I assume that planets and their satellites are created more or less at the same time. Why gaseous planets like Saturn have solid rings and satellites?

Is it possible to weight a gas in a container surrounded by a vacum? I am arguing with flat-earthers on how gas weight is determined. I just assumed that you can weigh a gas by placing it in a container on a scale inside a vacum. I think this was wrong. Can you do this or must you weight gas...

I apologize. I didn't see any general chemistry categories, so I am posting my question here. Microbes and methane are inextricable from one another. My question is this. Are microbes "encased" in gases like methane when they rise into the atmosphere? Surely microbes can become particulate...

I can’t quite work my head around this question, I am having a difficult time analyzing the question, I can’t seem to make out what the initial and final conditions are would appreciate all the help I could get cheers

(The equation of ideal gas is PV=NRT.if P=1atm,N=1mole,T=0°K,R=gas constant then volume = zero. Hence, the volume of an individual molecule of ideal gas is zero) An individual molecule of ideal gas is assumed to have zero volume. The molecules of ideal gas are assumed to be dimensionless points...

It takes energy to compress an ideal gas, and that same amount of energy is output as heat. But we also gain the potential energy of the compressed gas. It seems to me that we are doubling up our energy. Can anybody explain in simple, practical terms (to a humble mech engineer) how this works...

Hello, I am currently working on a research project that involves filling a 10L tedlar bag with about* 8 liters of methane gas from a compressed gas cylinder. I'm trying to work out the best way to fill the bag with a reasonable degree of accuracy while also minimizing (or hopefully avoiding...

Every morning I boil two eggs for ten minutes. My gas canister emptied faster than I thought it would. Now I had noticed that most of the air heated by the gas never touches the pot. I had another burner with half the diameter of the one I had been using. That means 1/4 the circumference...

I have a vacuum chamber of volume V connected to a vacuum pump via a tube of radius R and length L, and I want to design this "tube" such that R can be controlled in order to provide a constant rate of pressure change inside of the chamber of 2.5 mbar/sec, from atmosphere down to ~0.5mbar...

The volume of the cylinder is ##V=\pi r^2 h=\frac{7\pi}{250}\ m^3## the number of moles is ##n=\frac{15}{16}\ mol## so from ##PV=nRT## we get ##P=\frac{nRT}{V}=25975.5\ Pa##. Now, for the second question, it should be an isochoric process so ##V_2=V_1## and ##P_2=P_1+0.8P_1=\frac{9}{5}P_1## and...

Suppose there is a pressurized gas canister in space, at rest. With a mass "m" of gas inside of it at a pressure "P". Next the valve of the canister is opened. The canister will accelerate in the opposite direction to the valve opening. When all the gas has left the canister, it will be moving...

I mean - when they form. What are typical gas densities at lunar crater rim when the crater is made by a comet? An asteroid? Both a comet and an asteroid, hitting Moon at several km/s, initially heat up to several thousand K, and even asteroid produces some vapour... at hypocentre. However, by...

Hi Everyone. Can anyone give me some hints which will point out how to solve this problem, particularly using 'the formalism of Ex 21.25'. I've kicked this around for a couple of weeks now and I haven't been able to come up with anything. Regards TerryW

Hi, I tried looking for similar topics but nothing really solved my problem. How can I calculate the average gas flow on a syringe that was compressed over time, if the starting and ending pressure and volume are known? I am guessing there must be an equation which can relate these variables...

I am studying Ideal Bose Systems (Chapter 7) from the book "Statistical Mechanics" by Pathria and Beale (4th Ed. - 2021). ##\require{physics}## ##\require{cases}## The authors have derived the following relations: $$\begin{align} \dfrac{P}{k_B T} &= \dfrac{1}{\lambda^3} g_{5/2}(z)...

Hello,everyone! Recently i am doing an experiments about electromagnetic induced transparency in 85rubidum gas. I have two light source,which use the polarization spectrom frequncy stablizaiton technology to make them stable.One is used for probing light,and the other one is used for coupling...

Hello : i was watching the news , and it was all about how Europe will start the coal factories again for energy generation had a question related to reduction of coal consumption for energy generation 1 ) could we use coal fine particles instead of chunks of coal that will burn more...

Hello, I am trying to solve a problem about an open Gas Turbine. The given information would be: - An open gas turbine draws in air from the surroundings having the m, cp, T1 and constant kL with the next values: , - The air flow is heat over natural gas supplied: - The pressure ratio is 𝜋...

Hello What experiment or observation shows that for atoms, molecules or masses of gas, there is attraction in the sense of Newton's law (universal attraction)? Bernadette

This is a thermodynamics question. A gas absorbs 10 000 J of heat , it releases 3000 J and does 2000 J of work. How much has the internal energy varied? So I did 10 000 - 3000 -2000 = 5000 J so internal energy decreases by 5000 J. But the correct answer is A) it increased by 5000 J . How ?

I assume we can work it out from X-ray emission detections, such as shown with the famous bullet cluster images.

Hi! I wanted to do some basic calculations for temperature T on a water-filled pot. I noticed something strange on my calculations, and couldn’t figure out what was wrong... So here it is: The ideal gas formula: k=PV The actual formula Relates equally the product PV with the a constant...

I don't know if this is really stupid, but why isn't Earth's core a gas considering that its hotter than the temperature at which each of the metals turn into a gas?

Rate of effusion

I will summarize briefly my reasoning for both letters, since the answer is immediately after that: A) The work is quasi-static, and the pressure is approximatelly constant and equal to the atmospheric pressure, so the works is $$W = -p\int dV = -p_{0} (V_{0}-V)$$ B) The work is fast, fast...