Nitrous oxide (gas) left in the E cylinder:255 or 400 L?

[ketap]

hi..i am reading again about nitrous oxide from various resources..something interesting popped out in my "journey"...i always read that when the tank contains only gas N2O, there should be only about 1/4 full (25% or 400L ) left in the cylinder when the pressure is < 750 psi..(Miller's textbook confirms this)
..ok, i have accepted this concept for long time, without asking how they got into this number..

..but then i read other resources yesterday , and i found a "calculation" about it and shows that it is actually 255 L left in the cylinder when the pressure <750psi. (FYI, Ehrenworth's and Dorse n Dorse confirm it too..Wow!)

p1x v1 = p2 x v2
750x 5 = 14.7 x v2 , V2 : 255 L

so, i need to ask you...which one is true?
does anyone know about how my previous recources (and Miller's )got that number (400L)?

please help..thx u
best regards, Ketap

---

Members don't see this ad.

 

[agammaglobulin]

E-Cylinder of Nitrous pressure only drops when 1/4 of tank is left. Starting volume is 1600L, so once pressure gauge falls below 750 you know you have roughly 400L left. I hope that helps.

 

[Random Anesthesiologist]

You mean dorsch and dorsch?

 

[ketap]

hi...thanks for replying..

Random resident: yeah,..i guess i made typos when i wrote that..thanks for correcting me..

hi,Aggamaglobulin: i do understand what you were saying...but u missed my point...

what i don't understand is how can they got the knowledge : "1/4 full (=25%)"?
on the other hand, in dorsch and dorsch's and Ehrenworth's books...it is clearly stated that it is supposed to be 255 L. (=16%)..
so which one is true? 25% or 16% ?

thank you..

 

[deleted171991]

Whatever Miller and Barash say.

You don't need this information except for exams, and the examiners won't write the questions based on Dorsch.

 

[agammaglobulin]

hi...thanks for replying..

Random resident: yeah,..i guess i made typos when i wrote that..thanks for correcting me..

hi,Aggamaglobulin: i do understand what you were saying...but u missed my point...

what i don't understand is how can they got the knowledge : "1/4 full (=25%)"?
on the other hand, in dorsch and dorsch's and Ehrenworth's books...it is clearly stated that it is supposed to be 255 L. (=16%)..
so which one is true? 25% or 16% ?

thank you..

400L, 25% is the exam answer.