Nitrogen dioxide (NO2) concentrations are measured in an air-quality study and decrease from 5 ppm to 2 ppm in 4 min with a particular light intensity.
(a) What is the first-order rate constant for this reaction?
(b) What is the half-life of NO2 during this study?
(c) What would the rate constant need to be changed to in order to decrease the time required to lower the NO2 concentration from 5 ppm to 2 ppm in 1.5 min?