Understand that at steady state, total mass in equals total mass out, and component mass in equals component mass out — so the outlet concentration is a flow-weighted average of the inlet concentrations, not a simple average.
Total mass balance: F3 = F1 + F2Component mass balance: F3·x3 = F1·x1 + F2·x2Outlet concentration: x3 = (F1·x1 + F2·x2) / (F1 + F2)Keep the default streams: F1 = 10, x1 = 0.2, F2 = 10, x2 = 0.8. Confirm the outlet concentration is exactly the average of the two: 0.5.
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