Gas Definition and 1000 Threads

Homework Statement (introduction course of university physics)[/B] A 5.0- liter gas tank holds 1.7 moles of monatomic helium (He) and 1.10 mole of diatomic oxygen (O2), at a temperature of 260 K. The ATOMIC masses of helium and oxygen are 4.0 g/mol and 16.0 g/mol, respectively. What is the...

"KE=3/2nRT=3/2kT" is applicable to only monatomic gas or all kind of gas? What about " KE=1/2*fkT" ? (f: degree of freedom) Is it implies the same thing as "KE=3/2nRT=3/2kT" ? Thank you.

Say we have a tire filled with air (equal to ambient air surrounding it in every way). pressure on the gauge is 0. Then, we pressurize it to 1 ATM (15psi). If we heat the tire , the air will be heated and expand based on gas law, or is there a factor that changes it based on the air's...

Hello I'm looking for a graphical software to simulate a gas sensor mechanism. I thought "comsol multiphysics" could help me to determine the sensing mechanism of semiconductor gas sensor , but I didn't find any thing about this. I would appreciate you If you recommend an appropriate application...

Homework Statement We are asked to derive the expression for the internal energy of an ideal Fermi degenerate gas using Sommerfeld expansions, writing out terms up to the fourth order in ##(\frac{T}{T_F} )## , that is, we must determine ## \alpha ## in the following expression: $$ U=...

Homework Statement The question asked me to show that the entropy of a fermionic gas is ##S = -k_B \Sigma_i (1-f_i)\ln(1-f_i) +f_i\ln(f_i)## Using the Fermi-Dirac distribution so ##f_i = \frac{n_i}{g_i}##. Homework EquationsThe Attempt at a Solution The number of microstates ##\Omega## is...

Does anyone here have any experience with GC? I am developing a method for analyses and I understand all the settings but there is one related to the TCD called Temperature(pre). Does anyone have any ideas? Thanks for any suggestions!

I have a question in regards to a specific situation and really don't know which elements are significant. The example is high pressure AIR (a real gas/ not ideal ;-) of relatively unlimited volume, released via a rupture diaphragm into an enclosed tubulation. (dead ended) Relative dimensions...

Does energy have different states analogous to the solid, liquid, gas, and plasma states of matter? Would they be the same as "forms of energy" described here? https://en.m.wikipedia.org/wiki/Forms_of_energy

Hi guys! I have a problem with this exercise: 1. Homework Statement The stars called white dwarfs may have inside them a density in order of 1011 kg m-3. For semplicity, we assume: these stars are made with non interacting protons and electrons at the same quantity and with uniform density...

Hi all, I need to estimate the mechanical work I can recover from expanding hot air through a gas turbine. So far I am using the equation below, where Wrev is my ideal isentropic work, s the number of stages, n = k = ratio of specific heats, R gas constant, T1 is the inlet Temperature, Pin the...

hello :) when gravity overcomes the outward force of gas in a nebula as it collapses what exactly is this outward force of gas its overcoming ?

Homework Statement Explain why the gas becomes conducting only when the electric field in the tube reaches certain value? 2) why does fields does from higher potential to lower potential? Homework Equations F=QE The Attempt at a Solution If we increase the E then the Force will also increase...

Homework Statement Mass =0.908kg Area= 5.3 x 10^-4 m^2 2. Attempt This was for a lab I am doing on gas laws. Its asking to calculate exerted pressure in kPa. This is what I've done so far : F= 0.908kg * 9.8m/s^2 = 8.8984N Pressure = Force/ Area Pressure= ( 8.8984N) /( 5.3 * 10^-4...

Homework Statement Homework Equations and the attempt at a solution:[/B] AC is adiabatic and AB is isothermal. Heat absorbed during process AC = 0 (adiabatic). Heat absorbed during process CB = C_p \triangle T=-\frac{\gamma}{\gamma -1} (P_2V_3 - P_2V_2) Heat absorbed during process BA =...

Ideal gas behavior condition is high temperature and low pressure, right? so is the book's answer to 10(a) ii wrong? https://scontent-kul1-1.xx.fbcdn.net/v/t34.0-12/14996536_1455768127770250_1228715611_n.jpg?oh=750e2555f8229aa9a4eeb17e3e80b1fb&oe=5829A2EE...

Hello all, You all have always kindly helped me as I remember questions I have accumulated since high school days, and have never been answered. Eventually I gave up and forgot them, but as I grow old for some odd reason these things pop back up in my mind, like old ghosts from 35 years ago...

I am doing some multi-fluid hydrodynamic modelling and I have a quick question. I think I know the answer, but I am not convinced. One of the things that I need to know is the specific heat ratio, ##\gamma##, for the gas and my question is, how does one calculate this from the values of each...

Homework Statement An isolated box contains two chambers separated by a thermally insulating but moveable partition. Both chambers contain dilute gas (same kind) at different densities and temperatures. The left chamber contains 1.0 x 10^22 particles at 25 degrees celsius and the right chamber...

Homework Statement A fuel gas consists of 75% butane (C4H10), 10% propane (C3H8) and 15% butene (C4H8) by volume. It is to be fed to the combustion chamber in 10% excess air at 25°C, where it is completely burnt to carbon dioxide and water. The flue gases produced are to be used to generate 5...

Homework Statement Two moles of a monatomic ideal gas are at a temperature of 300K. The gas expands reversibly and isothermally to twice its original volume. Calculate the work done by the gas, the heat supplied and the change in internal energy. So: T = 300K; ΔT = 0 n = 2; R = 8.314 J K-1...

when do we use W=p dV and W= nRT ln Vi/Vf? i want to know because i got 2 different answer when i use them in the same question

I'm an undergraduate taking a physical chemistry course, and I got to a part in my reading about the derivation of the ideal gas law. The passage is linked below...

I am looking over the kinetic theory of gases. It is most commonly described as U = (3/2)*N*k*T = (3/2)*mass*R*T for a monatomic gas, assuming the gas is ideal. This is based on the derivation, where ultimately (3/2)*P*V = N*K = total kinetic energy of particles. My question, for a real gas...

Hi I was perplexed as to why the area on which the pressure acts is 'piR^2'. Since one complete half of the sphere is in contact with the gas, hence the pressure should be 4piR^2/2 (half of the surface area of sphere i.e 2piR^2)

The accepted explanation for the existence of water as a liquid involves hydrogen bonding. Why is this phenomenon absent in the case of hydrogen sulphide?

Homework Statement A generalized TdS-equation for systems of several types of "work-parts" and varying number of particles in multiple components, is given by dU = TdS + \sum_{i}y_idX_i+\sum_{\alpha =1}^{c}\mu_\alpha dN_{\alpha} Thus, its natural to regard the internal energy U (an...

Homework Statement For a diatomic gas near room temperature, the internal partion function is simply the rotational partition function multiplied by degeneracy ##Z_e## of the electronic ground state. Show that the entropy in this case is ## S = Nk\left[ \ln \left(...

What happens to ethanol vapor in an enclosed space like a room? Does it end up dissolving, or accumulating somewhere like the floor or towards the ceiling? If it does dissolve how long does it take?

Homework Statement The temperature across the capillary with constant cross-sectional area and length L is given by ##T=T_0e^{-kx}##. Assuming an ideal gas and constant pressure show the number of moles to be: $$n=\frac{PV(e^{kL} - 1)}{RkLT_0}$$ Homework Equations ##PV=nRT## The Attempt at a...

Homework Statement [/B] There is a lid on a .25m diameter, .30m tall cylindrical container enclosing .021kg of air. The lid is held in place solely by atmospheric pressure. It take 220N of force to pull of the lid at an atmospheric pressure of 101kPa. What is the Temperature of the enclosed...

Would it be possible to couple and electric motor to gas engine in series so both would increase the overall power.I currently building a twin engine car with two gas engines coupled together crank to crank like the old school twin dragsters.I would like to connect a large D.C. Motor in front of...

I have been given an assignment to use a specified distillation column to separate out propene from a gas. The gas consists of propene, propane, ethane and CO2. Separating out the propane has been straight forward, but ethane and especially CO2 are giving me a hard time. To make matters worse, I...

Homework Statement Show that for a gas obeying the van der Waals equation ##\left(P+\frac{a}{v^2}\right)(v-b)=RT##, with ##c_v## a function of ##T## only, an equation for an adiabatic process is $$T(v-b)^{R/c_v}=constant$$ Homework Equations ##TdS=c_vdT+T\left(\frac{\partial P}{\partial...

Homework Statement When, using a eudiometer in a lab to collect gas over water, if you have to switch eudiometers is the final volume of water displaced equal to the water displaced in the first tube + the water displaced in the second, and would the pressure be calculated through the total...

Homework Statement n moles of an ideal gas are placed in a frictionless piston with weight ##w_p## and cross-sectional area ##A##. The quantity ##\gamma = \frac{c_p}{c_v}## is a constant, the gas is originally at equilibrium values##(P_i, V_i, \theta_i)## and the external pressure is taken to...

Homework Statement To solve this problem you will need to construct a differential equation. A picture of the situation will help. Ignore all gravitational forces. A Rocket ship of structural mass M and fuel mass m, begins at rest relative to a gas cloud. The ship burns fuel at the rate ω which...

Homework Statement Why is the EA of Neon endothermic even though it has a high Z eff? Basically, what makes a full valence shell so stable? The attempt at a solution I know it has to do with shielding, core e-, and valence e-. But I don't know how to word it.

Homework Statement [/B] 1 mol of gas at temperature T is contained in a cubic container of side L. Estimate the number of collisions per second between the atoms in the gas and one of the walls of the cubic container. My book gives this formula for that quantity \frac{N_A}{6L}\sqrt{\frac{3 k...

I'm a first year electrical engineering student and in my General Chemistry class, every other week, we're required to write a paragraph about how each weeks material relates to your future career. As I am in electrical engineering, I don't see much relation to any topic. This week is...

I have a question regarding an occurrence with Nitrogen gas and two separate containers. I'm trying to explain why when I fill my steel pressure vessels to ~180psi on an avalauncher from a larger 2000psi steel tank, the pressure slowly drops to ~175psi after the fill. I believe this to be...

I know that this topic has already been covered (kind of) in a separate forum post, but it became rather confused and there were many differing and contradicting opinions/supposed facts, so I just want to clarify a few things. Firstly, are gas turbines more or less efficient (useful mechanical...

Homework Statement An ideal gas with adiabatic index γ is taken around a complete thermodynamic cycle consisting of three steps. Starting at point A, the pressure is increased at constant volume V1 from P1 to P2 at point B. From point B to point C, the gas is allowed to expand adiabatically...

Hello, Given: A large pressurized container with a small hole in a side. The sides of the container are VERY thin such that the thickness of the sides can be ignored. The pressure difference between the container and the environment is not large enough to result in choked flow. The outflow...

I am building a Rapid Pulse Carbonation prototype Reactor unit, I am capturing the Steam form the process and passing it though a Plate and Tube condenser to produce water, also I will capture the CO2 gas from the heating system. How would I reduce the exhaust gas heat before I pass the exhaust...

East Coast faces gas shortages, price hikes after pipeline leak (CNN.com) That pipeline passes about 20-30 miles from here. This morning I stopped at my usual gas station, one of the cheapest around here. There were more people there than usual, and a couple of the pumps had gone empty. While...

Assume: Hydrostatic Situation, ideal gas Use empirical formula T = T0 - Bz I have rechecked my work several times and can't seem to find a mistake. The answer is supposed to be: p2 = p1((T0 - Bz)/T0)(g/Bz) dp/dz = -ρg Now substitute ideal gas equation for ρ dp = -(p/RT)g dz ∫(1/p) dp...

Hi, are there any experimentalists here? I have gas in a cylinder. I have just been taking samples of gas from a tube connected to the outlet, but air is getting in the syringe. So I went over to chemistry and got a round bottom flask with 3 inlets / outlets and a septum, so its like this: I...

I understand that pure water that's being aerated will only take up just so much dissolved oxygen (DO) and that that depends on the temperature of the water. I see ranges of 14 ppm at close to freezing and around 6 ppm at 50 C as normal maximums. I understand, too, that you can temporarily...

We discovered a leak in a SF6 gas HV circuit breaker. Since we don't know when the leak occurred due to temperature changes I assume there is only air left in the tank. Here is my question. Suppose I have a tank with a fixed volume filled with air at the same pressure as the atmospheric...