Can internal pressure be equated to gas flow rate?

[inuyasha10121]

Hello, first post here. I had a bit of an odd question that I can't get my head around, but I think is possible. Given the environment described in the picture, can you measure the amount of gas that is flowing from the hole in the box given that the pressure in the box has stabilized at a specific value? I don't even know if its possible for the pressure to stabilize, but assuming that the solution is producing a steady amount of gas and that the reaction is never ending, can the internal pressure be equated to the flow rate given a set hole surface area, box size, and conditions externally being at STP?

My thoughts: It seems to me that this is a sort of modified venturi meter, or that Bernoulli's principle should be applied, but I just wanted to get a few opinions on the matter.

 

[Chestermiller]

This OP is looking for the relationship between flow rate and pressure drop for an orifice. Google orifice coefficient.