Are these gas density calculations correct?

  • Thread starter Thread starter kinogram
  • Start date Start date
  • Tags Tags
    Density Gas
AI Thread Summary
The discussion centers around the application of the ideal gas law, expressed as n = PV / (R/T), to calculate the molar density of hydrogen (H2) under specific conditions. The individual gas constant for H2 is noted as 4124 J/kg K. Two scenarios are presented: one where H2 is at standard atmospheric pressure (101325 Pa) and 273.15 K, yielding a molar density of 0.089949, and another at extremely low pressure (5 x 10^-18 Pa) and low temperature (2.7 K), resulting in a molar density of 4.49 x 10^-22. The discussion highlights an initial algebraic error in the equation format, clarifying that the correct form is PV = nRT, leading to the conclusion that the calculations for molar density were executed correctly based on the proper equation.
kinogram
Messages
24
Reaction score
0
If the equation below is correct

n = PV / (R/T)

where :

n = gas density in mole / m³
P = pressure in Pascal
V = volume in m³
R = ideal (individual) gas constant
T = temperature in Kelvin


Given that the individual gas constant - R for H2 = 4124 J / kg K

Then 1 m³ of H2 at 101325 Pa and 273.15 K
should have a molar density of 0.089949

and

1 m³ of H2 at 5 x 10-18 Pa and 2.7 K
should have a molar density of 4.49 x 10-22


are these calculated results correct?




.
 
Chemistry news on Phys.org
kinogram said:
If the equation below is correct

n = PV / (R/T)

where :

n = gas density in mole / m³
P = pressure in Pascal
V = volume in m³
R = ideal (individual) gas constant
T = temperature in Kelvin


Given that the individual gas constant - R for H2 = 4124 J / kg K

Then 1 m³ of H2 at 101325 Pa and 273.15 K
should have a molar density of 0.089949

and

1 m³ of H2 at 5 x 10-18 Pa and 2.7 K
should have a molar density of 4.49 x 10-22


are these calculated results correct?




.

There is an algebra error in your starting equation... See http://en.wikipedia.org/wiki/Ideal_gas_law
 
Thanks.. I see that now



PV=nRT

Then

n=PV/(RT)


however it looks like the calculations were made correctly according to the proper equation






.
 
Last edited:
It seems like a simple enough question: what is the solubility of epsom salt in water at 20°C? A graph or table showing how it varies with temperature would be a bonus. But upon searching the internet I have been unable to determine this with confidence. Wikipedia gives the value of 113g/100ml. But other sources disagree and I can't find a definitive source for the information. I even asked chatgpt but it couldn't be sure either. I thought, naively, that this would be easy to look up without...
I was introduced to the Octet Rule recently and make me wonder, why does 8 valence electrons or a full p orbital always make an element inert? What is so special with a full p orbital? Like take Calcium for an example, its outer orbital is filled but its only the s orbital thats filled so its still reactive not so much as the Alkaline metals but still pretty reactive. Can someone explain it to me? Thanks!!
Back
Top