What is the volume of fluid that must flow through the semipermeable membrane?

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The discussion centers on calculating fluid transport through a semipermeable membrane between two reservoirs at constant osmolarity. The initial assumption was that a current of 1 microampere (1 uA) equates to 1 micromole per second of ion flow, leading to a calculated transport of 0.1 microliters of solution per second based on a 1000 mOsm/l concentration. However, the poster encountered discrepancies when applying actual values of 100 uA and 300 mOsm/l, resulting in unexpectedly high fluid transport rates. The issue was traced back to an error in converting Coulombs to moles, specifically not using Faraday's constant correctly. The corrected conversion indicates that 1 uA corresponds to approximately 1.04 x 10^-5 micromoles per second of charge flux.
Andy Resnick
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I think this is a simple problem to solve, but I keep getting nonsense answers.

The question: two reserviors held at constant osmolarity (say 1000 mOsm/l) are connected by a semipermeable membrane. A current of 1 uA is measured across the membrane. What is the volume of fluid that must flow through the membrane?

So I have 1 uA = 1 umol/s ion flow, and 1000 mOsm/l means that 1 umol of osmolyte corresponds to 10^-7 liters of solution. So, 0.1 ul of solution is transported per second. Is this correct?

The reason I think I'm having trouble is that using my actual numbers (100 uA, 300 mOsm/l) I get very high fluid transport rates. Much higher than what is observed.
 
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Never mind- I found the error. It was in converting Coulombs to moles- I was not using the correct conversion (Faraday's constant).

1 uA corresponds to 1.04 *10^-5 umol/s of charge flux, in case anyone is interested.
 

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