the indicator dilution method is a technique used to determine flow rates of fluids in channels for which devices like rotameters and orifice meters cannot be used. a stream of an easily measured substance is injected ino the channel at a known rate, and the tracer concetration is measured at a point far enough downstream of the injection point for the tracer to be completely mixed with the flowing fluid. the larger the flow rate of the fluid, the lower the tracer concertation at the measurement point. a gas stream contains 1.50 moles co2 flows through a pipeline. twenty 20 kilograms of co2 per minute is injection point an found to contain 2.3 mole % co2.

a) estimate the gas flow rate (kmol/min) upstream of the injection point.

b) eighteen seconds elapse from the instant the additional co2 is first injected to the time the co2 concentration at the measurement points begins to rise. assuming the tracer travel at the average velocity of the gas in the pipeline estimate the average velocity (m/s). if the molar gas density is 0.123 kmol/m^3, what is the pipe diameter?