Acturally it\'s an environmental problem Select all that are True. Combustion so

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Acturally it's an environmental problem

Select all that are True. Combustion sources, such as cars and coal-fired power plants emit mainly NO_2. Combustion sources, such as cars and coal-fired power plants emit mainly NO The relationship [O_3] = (k_1-NO_2])/(k_3-[NO]) is known as the photostationary state relationship. The higher the ratio of [NO_2]/[NO] - the lower the concentration of O_3 The higher the ratio of [NO_2]/[NO] the higher the concentration of O_3 The relationship [O_3] (k_1-[NO])/(k_3-[NO_2]) is known as the photostationary state relationship.

Explanation / Answer

The Nitrogen oxides are released into the troposphere from variety of sources including fossil fuel combustion, biomass burning, microbial activity in soils and lightning discharges.

Common Nitrogen oxides are (NO and NO2). In the troposphere NO2 is photolyzed to NO with subsequent regeneration of NO2via reaction of NO with ozone.

                    NO2    +   hv     ---k1--->    NO   +   O(3P)   Rate = k1[NO2]

                    O(3P)   + O2---k2--->    O3                                  Rate = k2[ O(3P) ] [O2]

                           O(3P)    ---k4--->    O + hv               Rate = k3[ O(3P) ]

                     O3        +   NO    ---k3-->     NO2   + O2          Rate = k4[O3][NO]

With the ambient sunlight and abundant concentration of NO,NO2 and O3 is available the photo chemical stationary state(photostationary state) is achieved.

The net rate of formation of O3 is

                            d[O3] / dt = k2[ O(3P) ] [O2] - k4[O3][NO]

In steady state, d[O(3P)] / dt = 0, so

                            0 = k1[NO2] - k2[ O(3P) ][O2] - k3[ O(3P) ]

                       [O(3P)] = k1[NO2] / k2[ O(3P) ] + k3[ O(3P) ]

at photostationary state d[O3] / dt = 0

                      [O3] = k2[ O(3P) ] [O2] / k4[NO]

Substituting O(3P)] on the above equation,

                     [O3] = k2[O2] / k4[NO] (k2[O2] + k3) (k1[NO2])

                     [O3] = k1[NO2] / k4[NO]( 1 + k3/k4[O2])

The concentration of oxygen is very large so ( 1 + k3/k4[O2] )= 1

Then,

                   [O3]     = k1 [NO2 ]    / k4 [NO]

So the relationship

       [O3]     = k1 [NO2 ]    / k3 [NO] is the known as photostationary state relationship.

As we can see from the above equation NO2 produces O3 thus increasing the concentration of O3and NO produces NO2 on reacting with O3 thus decreasing the concentration of O3.

So, higher concentration of NO2 implies higher concentration of O3,

Thus, Higher the ratio of [NO2] / [NO] higher the concentration of O3

So, the options 1,2,3 and 5 are True.

        

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