Tiêu đề DPP 1 Solutions.pdf ✅

Class : XIth Subject : CHEMISTRY Date : DPP No. : 1 1 (c) NO,NO2,SO2 and SO3 are responsible for smog (environmental pollution). 2 (c) In troposphere, as we move towards the altitude, the density and pressure of air decreases. Due to which temperature also decreases 4 (c) Oxygen gas does not absorb I.R. radiation of high wavelengths reflected back by earth, hence it does not cause ‘green house effect’. 6 (c) SO2 affects larynx, between SO2 and SO3, SO3 is more harmful air pollutant and between N O2 and NO, NO2 is more toxic. Photochemical smog is caused by oxides of nitrogen 9 (d) When climate is warm, dry and sunny, the oxides of nitrogen and unsaturated hydrocarbons are converted in the components such as PAN, formaldehyde which form photochemical smog, by the action of sunlight 11 (c) One chlorine free radical can convert about one lakh ozone molecules into oxygen 12 (c) Chlorofluorocarbon is used in air conditioning and in domestic refrigerators for cooling purposes. Its main drawback in this, it is responsible for ozone depletion. 13 (b) We know that, O3 +CCl2F2→2OCl + F2O . Thus, in this reaction OCl is produced. 20 (c) The average residence time of NO is 4 days Topic :- Environmental Chemistry Solutions