Two Compartment Exchange Calculator
Calculate closed-system concentration exchange between two well-mixed constant-volume compartments.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Keep both volumes fixed by equal counterflows and solve the single exponentially decaying concentration difference.
Mean=(V1C1+V2C2)/(V1+V2); difference(t)=(C1−C2)exp(−q(1/V1+1/V2)t)
Worked example
Equal100 L compartments starting10/0 mg/L conserve mean5 mg/L.
Assumptions and input details
Closed, fully mixed, nonreactive dissolved material, equal simultaneous counterflows and constant volumes. No diffusion boundary layers, adsorption, dosing instructions or environmental suitability claim.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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