2. Calculate the number density of CO2 (365 ppm) in the atmosphere at ground level (P = 984 hPa, T = +18 C). Consider the following chemical mechanism for the production of hydrogen peroxide (H2O2) in the absence of nitrogen oxides (NOx) where all the rate constants are computed at a pressure of 1 atmosphere and a temperature of 298 K: 4 Reaction 1: 03 + hv 01D +02 k = 4.5 x 10-5 5-14 Reaction 2:01D +M 03P+M k2 = 2.9 x 10-11 cm molec.15-14 Reaction 3: 01D + H2O 20H k3 = 2.2 x 10-10 cm3 molec. -' 8-14 Reaction 4: OH +03 HO2 + O2 k4= 6.7 x 10-14 cm molec.-15-14 Reaction 5: H02 +03 OH + 202 ks = 2.0 x 10-15 cm molec. 1 5-12 Reaction 6: HO2 + HO2 > H2O2 + O2 ko =2.7 x 10-12 cmmolec.? (a) Write out the steady-state expressions (i.e., production rate = loss rate) for O'D, OH and HO2. s- (b) Using the steady-state equations in (a), show that d[H2O2]/dt can be expressed as a function of [O3], [M], and [H2O]. (c) Using the d[H2O2]/dt equation derived in (b), calculate the initial rate of H2O2 production for the following conditions: [M] = 2.5 x 1019 molecules cm"}, [O3] = 40 ppb, and [H2O) = 1.1 x 107 ppb. =