Question

number 10.

9. What is the weather and climate? 10. What is the free radicals in the atmosphere? Give some examples. What is the exited atom in the atmosphere? Give some examples 11. What are aerosol, condensation aerosol, and dispersion aerosol?

Answer 1

ANS-10.In chemistry, a radical (more precisely, a free radical) is an atom, molecule, or ion that has unpaired valence electrons or an open electron shell, and therefore may be seen as having one or more "dangling" covalent bonds.

***********The most common radical in the lower atmosphere is molecular dioxygen.  Photodissociation of source molecules produces other free radicals. In the lower atmosphere, the most important examples of free radical production are the photodissociation of nitrogen dioxide to give an oxygen atom and nitric oxide which plays a key role in smog formation—and the photodissociation of ozone to give the excited oxygen atom O.

*************In the upper atmosphere, a particularly important source of radicals is the photodissociation of normally unreactive chlorofluorocarbons (CFCs) by solar ultraviolet radiation, or by reactions with other stratospheric constituents (see eq. 1 below). These reactions give off the chlorine radical, Cl•, which reacts with ozone in a catalytic chain reaction ending in Ozone depletion and regeneration of the chlorine radical, allowing it to reparticipate in the reaction ( Such reactions are believed to be the primary cause of depletion of the ozone layer and this is why the use of chlorofluorocarbons as refrigerants has been restrictedTHANK YOU VERY MUCH

Date- Page: Sunlight No . Excited ho - Sunlight In lower atmosphere Example of excited atom in Atom No to Atmospher ② oxygen atom (2) 0+02 Sunlight 03 ( chlorine atom No, to sunlight No +03 No +0 NO + O2 In upper atmosphere * CFCs no cio chlorine free Radical 0 cl +03 10. + O2 & decomposition of ozone layer @ 03 - 02 to o ot cloo cito 4 203 to 302 Excited State of atom in atmosphere in upper atmosphere molecule abosorb Certain Amount of light (Energy) and goep in excited State (high Energy level Example Sunlight Oto - 135-167 km oxygen atom Othv (otte excited atom of oxygen 135-167um.