Questions tagged [gas-laws]
Physical and chemical laws describing the properties and behavior of gases. This tag currently applies to properties and laws concerning both ideal and real gases.
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Is the compression factor of a gas equal to Vm/Vm-b?
According to the definition, the compressibility factor is the ratio of the molar volume and the molar volume if the gas behaved as an ideal gas
$$ Z = \frac{V_\mathrm{m}(p,T)}{V_\mathrm{m}^\pu{ig}(p,...
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How is the notion that gases expand to the containing volume fit with the concept of molar volume? [duplicate]
I have a question about the concept of molar volume of a gas, which is defined as the volume occupied per mole of molecules of the gas.
I don't know details about what a gas is at a deep level, but ...
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How to obtain the value of the gas constant R = 8.20574 × 10⁻² L atm K⁻¹ mol⁻¹
While reading a chemistry book, I saw a table of values of the gas constant for different units.
For example,
$$R=8.20574\times 10^{-2}\ \text{L}\cdot\text{atm}\cdot \text{K}^{-1}\cdot \text{mol}^{-1}\...
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According to PV=nRT,if we increase temp,no of moles will decrease,but no of moles is dependent on mass,mass is constant,then how can moles change?
We know the ideal gas equation is PV=nRT,then, according to this,if we keep Pressure,volume to be constant,then on increasing temperature,no of moles will reduce,this would mean that mass of matter or ...
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How can I find vapour properties of a compound molten salt?
I'm carrying out thermal-hydraulic simulations of the Aircraft Reactor Experiment (a nuclear molten salt reactor) based on circulating molten fuel salt: NaF 53 mol%, ZrF4 41 mol%, UF4 6 mol%.
While ...
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How do I go about calculating final temperature of tank draining at saturation?
I am working on calculating pressure in a tank where the fluid is sitting at its vapor pressure. For example, imagine a 12 in diameter 100 L tank of nitrous oxide at room temperature (745 psi vapor ...
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How to shift SO3/SO2 equilibrium?
I am struggling with a chemical equilibrium question and would appreciate some help. The question involves a closed system where the equilibrium
$$\ce{2SO2(g) + O2(g) <=> 2SO3(g)}$$
has been ...
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Find volume of methanol produced via reaction between carbon monoxide and hydrogen gases
Methanol is manufactured by the reaction of carbon monoxide gas with hydrogen gas. If a $95~\%$ yield is usually obtained, approximately how many liters of hydrogen gas at $\pu{350 °C}$ and $\pu{300 ...
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My experiemental density of H2 does not match the published data. What causes this discrpenecy?
I placed 1 gram of NaBH4 in a balloon and placed it over a glass round bottle filled with water and acetic acid. While secured, I emptied the balloon into the bottle and made sure to wash the inside ...
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In combustion method for analysing molecular formula of gaseous hydrocarbon, is pressure of the gaseous mixture always constant?
I understand the we have to look at the volumes, but the fact that volume of a gas is directly proportional to the number of moles of the gas holds only at constant pressure. Also we are applying Gay-...
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In gas law equations, if volume and temperature are directly proportional, why can't we write the equation as temperature divided by volume? [closed]
In gas law equations, volume, temperature, pressure and amount of substance may vary. In the simpler equations, like Charles' and Amonton's, temperature and pressure/volume are directly proportional. ...
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Dalton's law clarification
I'm looking at Elements of Physical Chemistry by Atkins and de Paula. In section 1A.3, they state Dalton's law as
The pressure exerted by a mixture of perfect gases is the sum of the pressures that ...
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Is oxyhydrogen lighter than air?
And, if so, how much lift does it produce per cubic meter?
(let's say at 290ish K and 150 meters above sea level)
For context, I'm taking an intro-level physics class. While I know what a joule is, I ...
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What ideal gas behavior is observed by a real gas that observes Boyle's law (at Boyle's temperature)?
Boyle's temperature is a constant for a particular gas. At this temperature the real gas behaves ideally.
So, does the real gas only follow Boyle's law at this temperature, or are all the gas laws ...
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Find the percentage of dissociation of nitrogen tetroxide given pressure, temperature, enthalpy and entropy
Given
$$
\begin{align}
\Delta_\mathrm f H^\circ(\ce{N2O4}) &= \pu{9.16 kJ mol^-1}
&\quad
\Delta_\mathrm f H^\circ(\ce{NO2}) &= \pu{33.18 kJ mol^-1}
\\
S^\circ(\ce{N2O4}) &= \pu{304.3 ...
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How to calculate composition of alcohol/water mixture to achieve given concentration of alcohol vapors in air for calibrating a DIY breathalyzer?
I made a breathalyzer using a MiCS-5524 gas sensor. I would like to calibrate it so it can be close to accurate. e2v technologies — MiCS Application Note 4, Using MiCS Sensors for Alcohol Detection (...
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Does carbon dioxide come out of solution on freezing?
Years ago in a lab where I was working someone had the excellent idea of cooling down their can of coke by pouring liquid nitrogen over it. The can exploded and resulted in quite a mess.
My question ...
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GLP mass to volume conversion problem (Rotary Meter)
this is my first post here on this forum.
I would like to share a question that is bothering me:
I have a gas powered system.
I would like to measure the total gas consumption in ...
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Does KE(avg) stay the same for ideal gas if the PV value changes?
We know that Kinetic Energy is a function of Temperature for an ideal gas.
So KE (1 Mole of gas) = (3/2)RT = (3/2)PV.
So it's said that even if P or V change their change will counteract the other (...
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What happened after fire finished burning? [closed]
After fire finished burning, did it merge with the atmosphere and becoming water vapors, oxygen and nitrogen, or did it simply disappear into nothing?
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Can we calculate final temperature of two gases in thermal contact? [closed]
This is a question from IIT-JEE - ADVANCE 2018
A closed tank has two compartments A and B, both filled with oxygen (assumed to be ideal gas). The partition separating the two compartments is fixed ...
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Why do we subtract the volume correction term in the van der Waals gas equation [duplicate]
The following equation is valid for ideal gasses
$$pV=nRT$$
Please mind the following notation, any parameter that is related to an ideal gas would be denoted with a subscript $i$ and anything related ...
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Confusion in Van der Waals Equation
I understand that the behavior of ideal gases deviates largely from that of real gases in terms of pressure exerted by the gas molecules on the container in which it is present, space available for ...
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On Van Der Waals relation: how to derive du/dv = a/v^2 without using the relation dU=TdS−PdV?
I have read several threads and papers which show how to derive $\left(\frac{\partial u}{\partial v}\right)_T = \frac{a}{v^2}$
by using the Maxwell's relation $\left(\frac{\partial{S}}{\partial{V}}\...
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Why is the excluded volume in van der Waals 4 times the actual volume of the gas molecule?
I am having trouble understanding why the excluded volume of a particle is four times its actual volume.
According to Wikipedia,
"The excluded volume b is not just equal to the volume occupied by ...
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How do you calculate the heat capacity ratio for a multi-compound gas?
Let's say I have a heat capacity ratio of 1.4 N2 and a heat capacity ratio of 1.2 for O2 (just random placeholder values no significance), and I wanted to calculate the heat capacity ratio of their ...
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How would one calculate the Heat Capacity Ratio for a multiple compound Gas?
So I'm attempting to calculate the heat capacity ratio (known also as adiabatic index) of a gas with several concentrations of different compounds such as N2, H2O, CO2, CH4 etc. And while I have an ...
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How to calculate corrected Gas Volume?
We are working on a project called 'Electronic Gas Volume Corrector'. The device reads pressure and temperature from sensors mounted on a gas pipe and gas volume from a gas meter. These are the ...
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Why is the value of the heat capacity ratio γ the same for molecules with the same atomicity?
The heat capacity ratio is defined as the ratio of the heat capacities at constant pressure and volume respectively:
$$\gamma = \frac {C_p}{C_V}\tag{1}$$
Then obviously
$$\gamma = \frac{n\,C_p\,\Delta ...
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Cubic nature of van der Waals' gas equation
$V_m^3-\dfrac{RT+bP}{P}V_m^2+\dfrac{a}{P}V_m-\dfrac{ab}{P}=0$
So, At $T<T_c$ the above equation has three real roots say $V_1,V_2,V_3$, my doubt is what does this mean physically because for some ...
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Can general purpose compressors be used for a specific gas without modification?
Air compressors are commonly used for all sorts of purposes related to compressing air above 1 atm. My question is, could an air compressor be used for a specific gas without modification?
For example,...
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Why should the cubic equation in volume, obtained from Van Der Waals equation of state, have equal roots at the critical point?
The video Edmerls —
Derive Equation for Critical Constants in terms of Vander Waal's Constants. | Physical Chemistry (YouTube) provides a derivation of the relationship between the van der Waals ...
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Balanced reaction to Cr given H+ [closed]
The troublesome nature of this post, is that I was given very little information to work with:
"The metal chromium (Cr) reacts with an acid, to create Cr^+3 ions, and hydrogen gas.
Show the ...
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Stratification of gasses by mass [closed]
Suppose a homogenous mixture of mutually non-reactive gases is isolated in a container so that there are no external kinetic forces (vibration or rotation) that create turbulence or other mixing ...
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If Graham's law doesn't apply to the ammonia and hydrogen chloride diffusion in a glass tube demonstration, is there a law that does?
A comment below What exactly are "white fumes" and why does holding a bottle of ammonia (conc) next to a bottle of HCl (conc) make them? links to The
Royal Society Of Chemistry video ...
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How to prepare standard sample of benzene for gas sampling bag?
I need to make a 1 ppm gaseous standard of benzene in nitrogen gas within a Tedlar® gas sampling bag. Is this as simple as injecting 1 μL of neat benzene liquid into 1 L of nitrogen gas within the bag?...
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Why is Molar Mass of a gas twice the vapour density?
I've seen this relation at a number of places, and I can't get why. A simple Google search doesn't give me a simple answer either.
Also, are there any exceptions/conditions for this relation to be ...
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What will happen in the volume occupied capacity of each gas when separator is removed? [closed]
Consider a situation where two gases occupying volumes $V_1$ and $V_2$ and having partial pressures $p_1$ and $p_2$, respectively, are kept separated in a rigid container. If the separator is removed, ...
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How to identify isochoric process from the problem's wording?
Problem 19 from NEET's Solved Paper 2013:
The amount of heat energy required to raise the temperature of $\pu{1 g}$ of helium at NTP from $T_1$ to $T_2$ (in kelvin) is
\begin{align}
&\text{(a)}~\...
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Why are certain gases with higher molar masses less dense than the ones that have a lower one?
Neon, despite having a larger molar mass than nitrogen, oxygen and fluorine, is less dense than all of them. This also goes that fluorine (again) and chlorine are both denser than argon, even though ...
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Could an LPG gas ever become lighter than air?
Both of the LPG gases, propane ($\ce{C3H8}$) and butane ($\ce{C4H10}$) are heavier than air. Propane is $1.55$ times heavier and butane is $2.08$ times heavier. Is same-temperature air always lighter ...
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If a = 0 for a Van der Waals gas, what does that signify?
I know that if $a = 0$ for a gas at certain temperature and pressure, it means that the molecules of gas have almost no attractive forces acting between them.
But does that also mean that the ...
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Can the expression be represented as a total differential?
I should determine whether the following expression represents a total differential:
$$\mathrm{d}f(x,y) = (\ln y) \,\mathrm{d}x + \frac{x}{y}\,\mathrm{d}y$$
But with the following method (physical ...
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Can a vacuum on a closed system really “pull” things out of it?
So I’m learning gas discharge tube making (neon) and there’s a step where you cork one end of the tube and pull a vacuum on the other end to suck out all the impurities. The same thing was done when I ...
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Formula for collision frequency and mean free path
We were studying collision frequency and mean free path today, and in it, we got the equations of collision frequency as:
$$Z=\sqrt 2 \pi \sigma^2v_{rms}N$$
where $N$ is the number density, equal to $...
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Is it appropriate to say "solid-in-gas solution" and "liquid-in-gas solution"?
A number of books mention "solid-in-gas" and "liquid-in-gas" types of gaseous solutions.
However, for something to dissolve in a gas, it must be in its vapour phase. So, for ...
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Is the value for the Boltzmann Constant different in 2D?
So I'm simulating some hard sphere collisions and want to determine the Boltzmann constant in two dimension, using the equation
$$PA=Nk_BT$$
where $A=\pi R^2_{container}$, $P=(averageImpulse/time)/(2\...
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What is reversible change for ideal gas?
What are the reversible and irreversible changes for an ideal gas? Is it the change that keeps the ideal gas law during the change? Is any reversible change a sum of changes satisfying the ideal gas ...
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why can water heated to a certain temperature in microwave explode when removing cup , bowl etc to room temperature air? [closed]
Studied a lot about $\mathrm{pH}$ , molecule dipoles properties $\ce{H2O}$. never saw anything along lines of energy storage, except ice contains heat energy , ionization of water always happens. ...
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Relationship of oxygen dissolved in water with bubble time and temperature
I'm using the Winkler method to calculate oxygen dissolved in water. This is at the temperatures 20, 30, 40, and $\pu{50 ^\circ{}C}$ and I bubbled a controlled amount of oxygen in through the reaction ...
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