nikotyna1939
Hazard to Self
Posts: 59
Registered: 26-9-2018
Location: reverse poland flag or nusantara
Member Is Offline
Mood: THINK 3R REDUCE REUSE RECYCLE
|
|
formula for calculating amount of compressed gas
i want to know what is the formula for calculating amount of compressed gas at 25 Celsius and 100 bar inside 10 liter gas cylinder filled with
methane, hydrogen and oxygen. also i mean how much cubic of gas can be filled inside the cylinder ,the purity is 100 percent and also each cylinder is
separate gas not mixed
[Edited on 11-4-2019 by nikotyna1939]
[Edited on 11-4-2019 by nikotyna1939]
|
|
|
Ubya
International Hazard
Posts: 1247
Registered: 23-11-2017
Location: Rome-Italy
Member Is Offline
Mood: I'm a maddo scientisto!!!
|
|
to answer i need the partial pressure of each gas.
what's the percentage of each gas?
---------------------------------------------------------------------
feel free to correct my grammar, or any mistakes i make
---------------------------------------------------------------------
|
|
|
Deathunter88
National Hazard
Posts: 519
Registered: 20-2-2015
Location: Beijing, China
Member Is Offline
Mood: No Mood
|
|
For a good estimate, this is not needed. Just multiply the pressure in ATM by the volume of the cylinder. In your case 100bar is about 99atm.
99atm*10L=990L of gas.
|
|
|
Ubya
International Hazard
Posts: 1247
Registered: 23-11-2017
Location: Rome-Italy
Member Is Offline
Mood: I'm a maddo scientisto!!!
|
|
| Quote: |
The general equation of state of an
ideal gas that is used in partial pressure mixing, Boyle's law, states that the quantity (P*V) is a constant at
constant temperature. This equation must be corrected to address the behavior of real gases under high
pressure. Thus the expression:
P1* V1 = P2* V2
needs a supplementary factor, the compressibility factor Z. If Z is less than 1 gases can be more easily
compressed than gases with Z values greater than 1. The equation of state now becomes:
(P1* V1) / Z1 = (P2* V2) / Z2
The Z value for oxygen at 165 bar (2400 psi) and 20°C is 0.941. Using the above equation, a gas cylinder
with a volume of 5.7 liters (~40 ft3
@ 3000 psig) filled with oxygen to 165 bar would contain the
equivalent of 999.5 liters of oxygen at 1 atmosphere instead of 940.5 liters calculated by the use of
Boyle's law.
|
It's not a good estimate multiplying the volume at a certain pressure for the new pressure, it's not that simple, otherwise PV=nRT would be already
more than enough for everything.
I thought nicotyna needed a better answer than "a bunch of gas"
---------------------------------------------------------------------
feel free to correct my grammar, or any mistakes i make
---------------------------------------------------------------------
|
|
|
Tsjerk
International Hazard
Posts: 3032
Registered: 20-4-2005
Location: Netherlands
Member Is Offline
Mood: Mood
|
|
Don't calculate, or has been measured.
First hit when googling "pressure density gas methane graph"
link
[Edited on 11-4-2019 by Tsjerk]
|
|
|
CharlieA
National Hazard
Posts: 646
Registered: 11-8-2015
Location: Missouri, USA
Member Is Offline
Mood: No Mood
|
|
Doesn't it say in the original post that each gas is in separate cylinder? In which case I would think that PV = nRT would apply.
|
|
|
Ubya
International Hazard
Posts: 1247
Registered: 23-11-2017
Location: Rome-Italy
Member Is Offline
Mood: I'm a maddo scientisto!!!
|
|
Quote: Originally posted by CharlieA  | | Doesn't it say in the original post that each gas is in separate cylinder? In which case I would think that PV = nRT would apply.
|
edited his post, in the beginning it sounded like it was just one cylinder with a mixture of gases
---------------------------------------------------------------------
feel free to correct my grammar, or any mistakes i make
---------------------------------------------------------------------
|
|
|
Plunkett
Hazard to Self
Posts: 96
Registered: 16-4-2017
Location: The Richest Hill on Earth
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by CharlieA | | Doesn't it say in the original post that each gas is in separate cylinder? In which case I would think that PV = nRT would apply.
|
The ideal gas law starts to fall apart at low temperatures/high pressures where intermolecular forces become more significant. There are equations
that accommodate for intermolecular forces (which I am not in the least bit qualified to talk about), but for more common gases like methane, hydrogen
and oxygen it is often easier to look up a chart like the one Tsjerk linked to.
[Edited on 12-4-2019 by Plunkett]
|
|
|
Texium
|
Thread Moved
13-3-2024 at 05:09 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
