While the answer to the title is inevitably "Yes", allow me to clarify. I have no background in physics, so please bare with me and I'll be happy to add any clarifications requested in the comments.

If I have 2 tanks:

  1. rated for 100,000 kPa, currently at 100,000 kPa, contains Gas#1
  2. rated for 2,000 kPa, currently at 1,000 kPa, contains Gas#2

Let's say hypothetically their valves are connected together with an infinitely strong pipe and some form of pressure regulator that prevents Tank #2 from being pressurized beyond 2,000 kPa. Let's also say the gases inside are of equal density/volume/weight/etc.

The question is:

If I opened the valves to these 2 tanks, and Tank #1 pressurizes Tank #2, will the gases exchange between the tanks? In other words, which one of these scenarios would be correct:

Scenario 1:

Tank #1 is now at 90,000 kPa, contains Gas#1

Tank #2 is now at 2,000 kPa, contains 50/50 Gas#1/Gas#2


Scenario 2:

Tank #1 is now at 90,000 kPa, contains Gas#1/Gas#2 (ratio unimportant)

Tank #2 is now at 2,000 kPa, contains Gas#1/Gas#2 (ratio unimportant)

Thank you in advance!

  • 1
    $\begingroup$ I think you may need to provide more detail on how the pressure regulator limits the pressure in tank 2. $\endgroup$
    – Bob D
    Feb 17, 2020 at 16:02

1 Answer 1


Note that two gas in cylinder will diffuse with each other and come to same pressure and temperature. Also will occupy whole volume of two container.

Mathematically finding pressure

$$P(V_1+V_2)=(n_1+n_2)RT$$(for final combination).

Now for final temperature $$n_1C_1(T-T_1)=n_2C_1(T_2-T)$$ Finally solving these $$P=(R(n_1T_1+n_2T_2))/(V_1+V_2)$$ Hope this helps you.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.