Gas Definition and 1000 Threads

Homework Statement Gas occupies 2m^3 at a pressure of 100kPa. What is the pressure when the volume is 1.5m^3 and the temprature is unchanged? Homework Equations p=nRT/V The Attempt at a Solution As a logic conclusion i took 1.5/2x100 and got 75 but 175 is not the answer.. The answer is...

Hello, I understand when you release a compressed gas generally it comes out cooler than atmosphere. But here are my questions: When you fill the container, the gas warms up as the pressure builds. Generally it takes a long time to compress and I believe the temperature of the gas when it's...

If we connect a two metals with different Fermi levels electrons will start to flow from metal with higher Fermi level to a lower one. Untill metal with lower Fermi level will get negatively charged and the process will stop. But what if we connect a two materials with different Fermi levels...

Homework Statement Derive from the formulas ##\frac{D^\pm}{Dt}(u \pm F) = 0## where ##\frac{D^\pm}{Dt} = \frac{\partial}{dt} + ( u \pm c) \frac{\partial}{\partial x}## the one-dimensional wave equation in the acoustical limit. \begin{cases} u << c\\ c \approx c0 = const\\ F =...

Homework Statement Homework Equations PV=nRT The Attempt at a Solution not sure if this is the right approach plugging into -ρg gives us -PMg/RT = dP/dy now we have to integrate both sides to find P?

First, may I apologize in advance if this question is in the wrong section of the forums. Given a cloud of mixed gasses and rocky material, how is spin created when a star is born? I will also give the cloud of gas a random order of movement prior to star formation. Can the physics for the...

Ponderomtive force is well known phenomenon, able to accelerate particles of all charges in plasma, but what about neutral gas? If we omit thermodynamics for a while and consider a perfectly non-ionizable gaseous dielectric, would polarisation be enough to induce motion in it? Thanks for...

This is just a qualitative question but feel free to show an equation if possible. Basically if you have a container with a heating element, let's say 500 W with a temperature of 2500 Kelvins and inside this box is a low pressure ideal gas, something like 1/100 of an atmosphere. Also imagine...

A cylinder containing oxygen gas O2 has a piston that can move unfazed by friction. The piston has a diameter of d = 16cm. The oxygen gas has a temp of 40,0 degrees Celsius and a pressure of 145kPa. The pressure outside the cylinder is 101kPa. The piston is held in a stationary position s =...

To obtain force from momentum we use the formula change in momentum/time. The time in the equation refers to the amount of time the force is exerted on the gas molecules. So when considering the kinetic theory of gases we are taught that F ∝ change in momentum/ time so F ∝ 2mv/(2d/v) and hence...

Good day, TiO2 have many possible application in material science, one of this is in Memory device, base on some literature TiO2 had a good chemical stability at high temp, so this is one reason why TiO2 is best candidate for this application, but beside of that, what other properties of TiO2...

Homework Statement An ideal monatomic gas is contained in a cubic container of size ##L^3##. When ##L## is halved by reversibly applying pressure, the root mean square ##x##-component of the velocity is doubled. Show that no heat enters of leaves the system.Homework Equations ##dU = dQ -pdV##...

I am studying National 5 physics, and my exam is tomorrow. I need some last-minute help. I'm struggling a little bit with the combined gas law, P1V1/T1 = P2V2/T2, and I'm not sure why. It would help me a lot if you could show step-by-step how the formula is used. Thanks for your time, it's very...

A question in regards to rolling resistance. Am I wrong in thinking that not everything you hit on the road with your tire effects your gas mileage? Don't tires have a tolerance in terms of how much energy they can absorb before it effects your traction, therefore effecting your gas mileage...

In nuclear physics we have talked about the liquid drop model and the fermi gas model. My question is can a Fermi liquid and a Fermi gas be directly described using these models? Are they the same thing? i.e. If I wanted to decribe the difference between a fermi gas and a fermi liquid could I...

Hello. Is there a way to calculate properties of a gas, given only it's composition? I.e. let's say i want to know what would a planet look like with an atmosphere of a mix of 50% gaseous sulphur and 50% gaseous mercury, at 500*C and surface pressure of half that of Earth. How would i go about...

Hey I've been thinking of this idea for a while, If I had a small boat with a home made gas turbine engine on it to power it solely with thrust. If I put an afterburner on it and nozzle; and had a small intake for water that filtered out all of the crud. Would it be possible to generate more...

Suppose I have a cylinder of gas and at time t=0 I can turn on a strong vertical gravitational force. Let the force change quickly (but a time long compared the mean free path divided by the average gas particle velocity) to reach some constant maximum value F(z,t) = F_max. (This force can be...

Can us generate electricity just from gas? I meant not by steam generator but by ionize gas,for example from original air gas?

I understand that gas flow through a circular tube or pipe will have some understandable effects... for example the pressure drops, and the maximum flow diminishes. I also know that turbulence and the tubing surface has an effect... Without getting too specific, I just want to understand...

So I'm trying to figure out the average energy of diatomic gas molecules via the equipartition theorem at high temperature (such that it's translational , rotational and vibrational modes are activated) and to do that I need to know the degree of freedom. some websites claim it would be 6 , 3d...

Homework Statement In an empty rubber raft the pressure is approximately constant. You push on a large air pump that pushes 1.0L (1.0×10^−3 m^3) of air into the raft. You exert a 16N force while pushing the pump handle 2.0×10^−2 m . Part A: Determine the work done on the gas. Part B: If all...

Homework Statement In an ideal gas at temperature T, the average force that a molecule applies on the walls of a closed container depends on T as Tq. A good estimate for q is: A. 2 B. 1 C. 1/2 D. 1/4 Homework Equations PV= nRT I think, Volume of container and moles are constant. So P ∝ T The...

Homework Statement Consider ##n## moles of gas, initially confined within a volume ##V## and held at temperature ##T##. The gas is expanded to a total volume ##\alpha V##, where ##\alpha## is a constant, by a reversible isothermal expansion. Assume that the gas obeys the van der Waals equation...

What can be done with the excess FCC flue gas from a fluid catalytic cracker

Homework Statement Given: Ideal gas equations: Find S(T,V) for an ideal gas Homework Equations Ideal gas equations: \begin{array}{l} {\rm{}}\\ U = \frac{3}{2}N{k_B}{\left( {\frac{N}{V}} \right)^{2/3}}\exp \left[ {\frac{S}{{\left( {3/2} \right)N{k_B}}} - {s_0}} \right]{\rm{ }}\\ T = {\left(...

Homework Statement Can someone confirm if I answered correctly? Thanks for support and help! a) In the Brownian motion experiment, small particles of matter are seen moving randomly. Give an explanation for this motion. b) Boyle's Law is fundamental when discussing the gas laws. i) State...

Hello, I know this has been fairly discussed to death, but I've had relative trouble finding a response that specifically addresses the n, in PV= nRT, the ideal gas law. Out of relatively common sense, by adding additional moles of gas, the pressure in the gas should increase as there are more...

Hello everyone! I am new here. I have used this forum on and off through google searches in the past and learned a fair bit from the posts. This is the first time asking anything. The question is probably extremely simple but has been overrun in my head for a week! It is in regards to...

Hey guys Don't know if this is posted in the right category. doing an technical report on industrial gas turbines. but i am kind of lost. Does anyone have any input to what we can write about? I'm thinking of any problems with the turbines that we can write about. What heat loss and how much...

Homework Statement \rho_0, c_0 is the mean density, the mean speed of sound in the ideal gas. Is the following correct? c(\rho)=c_0\left(\frac{\rho}{\rho_0}\right)^{\frac{\kappa-1}{2}} Homework Equations p = const * \rho^\kappa, c=\sqrt{\frac{\partial p}{\partial \rho}} The Attempt at...

Its given in my textbook that equivalence of gas = (volume of gas) / (Volume of 1 eq. gas at NTP) How do i calculate volume occupied by 1 equivalent of gas? Example: What would be the volume occupied by 1 eq. of CO2 (Its given 11.2l in my book) Is there a formula for this?

Homework Statement The cannon is made from V=30ml test tube completely closed with a plug (diameter d=1,5cm; length l=3cm; mass m=5g). Before closing the test tube, V'=1ml of water is poured into it. Room temperature is 20oC , pressure p=105 Pa , relative humidity is σ=20%. When the temperature...

Homework Statement The cannon is made from V=30ml test tube completely closed with a plug (diameter d=1,5cm; length l=3cm; mass m=5g). Before closing the test tube, V'=1ml of water is poured into it. Room temperature is 20oC , pressure p=105 Pa , relative humidity is σ=20%. When the temperature...

we can use avogadro's law and gay lussacs law to find atomicity of gases but what about solid elements

Hi there, I'm trying to clear up some misconceptions I have about emission spectra from various substances. Most of the discussion about gases focusses on the line emission spectra from a hot, low density gas due to electron shell transitions. But I also know that any charges that are made to...

F = Δp/Δt http://www.sumoware.com/images/temp/xzhhjttxobbodxgr.png (Sorry for bad sketch.. hehe) In the kinetic-molecular theory of gas, the Δp is -2mv (since it's supposed to be elastic collision) But, why the Δt is 2L/V ?? I think it must be a very small time (since the impact is done in a...

Homework Statement Just want to check that I've used the correct method for this thermodynamics question I've been set. Any clarification would be greatly appreciated. So I have 0.5kg of gas held in a rigid container of volume 0.25m^3 at a temperature of 20°C. 20kJ of heat energy is required...

In physics book, if work is done by the system, it is positive in my chemistry book, if work is done by the system, it is taken as negetive. when I asked my chemistry teacher, he said the sign convention is different in physics and chemistry. but why are they different?

Really simple question but it's been making me a little confused. Lets imagine we have a container (cubic with length of 1 meter) with a pressure of 1 Pascal and then an area inside the container of 1 mm^2 is chosen to measure the force on that area, what would the pressure be? 1 Pascal or...

Homework Statement Estimate partial pressure of nitrogen in atm in a room where you are at this moment. Use an ideal gas approximation and assume that air is composed of only nitrogen and oxygen. Show how you arrive the final answer in detail. Homework Equations pv=RT, while p stands for...

Hi I was wondering if anyone could tell me what gasses are absorbed between 800 and 1000nm wavelength and weather there is a book that lists all the gas wavelengths that can be absorbed in this region Thanks bertopolis

Hi I am new member ( mechanical engineer student ) , and the college just add a new course which is Turbo machinery , any way the teacher is new to the course & the quality of our teacher is not that good so , I was having a question and ask him but didnt get much from him so here I am ^^When...

Here is a screenshot from a page from a textbook that explains how to derive the ideal gas law: In the third bold line, I don't understand how "time" in force = (change of momentum)/(time) is equal to 2x/u (the time it takes for the particle to travel to the opposite face and back again) -- I...

Homework Statement Derive an expression for the change in internal energy of 1 mol of an ideal gas for expansion from volume V_i to V_f under constant pressure of 1atm where \gamma = \frac{C_p}{C_v}=\frac{5}{3} Homework Equations \Delta U=\frac{3}{2}nR\Delta T PV=nRT The Attempt at a...

Homework Statement At 1 atm and 0° C, a 5.04 L mixture of methane (CH4) and propane(C3H8) was burned producing 20.9 g of CO2. Assume complete combustion. 1. How many moles total of methane and propane were present before combustion? 2. How many moles of carbon dioxide were present after the...

Homework Statement A blackbody photon gas is contained within an evacuated cavity (V = 0.01 m^3). Calculate C_p for the photon gas at T = 1000K Homework Equations C_p - C_v = T(\frac{\partial S} {\partial V}) (\frac{\partial V}{\partial T}) C_v = T(\frac{\partial S} {\partial T}) S =...

Hi there, I'm considering how the ideal gas law applies in practice in our planet's atmosphere. In particular, I'm considering this form of the law: P = ρRT (1) where P is pressure, ρ is density, R is the gas constant and T is the temperature. I also know that, to a good approximation, the...

Greetings Everyone! I read a very good thread regarding how Ideal Gas Law is used to calculate system work for the electrolysis of water: W = PΔV = (101.3 x 103 Pa)(1.5 moles)(-22.4 x 10-3 m3/mol)(298K/273K) = -3715 J https://www.physicsforums.com/threads/work-of-electrolysis-of-water.756240/...

Homework Statement An air bubble of volume 3.0x10-5m3 escapes from a divers equipment at a depth of 45m where the water temperatures is 5 degrees C. What is its volume as it reaches the surface, where the temperature is 12 degrees C? Atmospheric pressure = 101kPa, density of sea water =...