Engineering, 01.03.2021 22:00 EinsteinBro

A 90-m^3 basement in a residence is contaminated with radon coming from the ground through the floor drains. The concentration of radon in the room is 1.5 Bq/L under steady-state conditions. The room behaves as a CSTR, and the decay of radon is a first-order reaction with a rate constant of 2.09 x 10^-6 s^-1. If the source of radon is closed off, and the room is vented with radon-free air at a rate of 0.14 m^3/s. Required:
How long will it take to lower the radon concentration to an acceptable level of 0.15 Bq/L?

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A 90-m^3 basement in a residence is contaminated with radon coming from the ground through the floor...