pona, units of mg/L? 4.2 A mixture of two gas flows is used to calibrate an air pollution measurement instrument. The calibra- tion system is shown in Figure 4.23. If the

calibration gas concentration Ceal is 4.90 ppm,, the calibration gas flow rate Qcal is 0.010 L/min, and the total gas flow rate Qtotal is 1.000 L/min, what is the concentration of calibration gas after mixing (Ca)? Assume the con- centration upstream of the mixing point is zero.