CO² concentration over time

[DieterVk]

Hi all,

I don't know how to calculate following problem:

Problem:
I have a room with a certain concentration of CO[sub]2[/sub]. There is a leak which causes the concentration to fall over time.

Known:
CO[sub]2[/sub] concentration start = 43.0%
CO[sub]2[/sub] concentration after 10 minutes = 22.2%
CO[sub]2[/sub] concentration air outdoors = 0.04%

Asked:
What should the initial CO² concentration be to have the minimal CO[sub]2[/sub] concentration after 10 minutes = 38% ?

Any help?

*edit*

 

[btrueblood]

You need two readings at two different times inside the room to establish the leak rate.

 

[DieterVk]

Now you have all the information.

 

[moon161]

This is comically ill defined for me, if the answer is to matter in some way. Why does the concentration change? Does the leak selectively permit C02 to leave? Is the CO2 diluted by infill? Is it a leak at the bottom of a chamber where C02 sinks to the bottom? These possibilities give different meanings and solutions to the problem.

A common engineering assumption would be that dC/dT is constant and that C(t) is linear and determine dC/dT from 2 points where the change in C and the change in time is known, and you're doing 7th or 8th grade math in the US, or 5th grade math in many other countries. That's as simple as it gets. Beyond that responsibility for passing on this, getting this right or wrong is yours.

 

[IRstuff]

Sounds like a homework problem to me

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[rb1957]

when you figure out the answer, let us know, please.

another day in paradise, or is paradise one day closer ?