Q.Compare classical smog and photochemical smog under three headings:

| Heading | Classical (London-type) smog | Photochemical smog |\n|---|---|---|\n| Chemical nature | Reducing ($\text{SO}_2$ is a reducing agent) | Oxidising (ozone and PAN are strong oxidants) |\n| Main pollutants | Smoke, fog, $\text{SO}_2$ (and derived $\text{H}_2\text{SO}_4$ mist) | $\text{NO}_x$, unburnt hydrocarbons, and the ozone/PAN they form |\n| Climate/season | Cold, humid, still winter weather, coal-burning industrial cities | Warm, sunny days, heavy vehicular traffic |\nThe two forms of smog share the property of forming under a temperature inversion that traps pollutants near the ground, but otherwise differ in essentially every respect: which …

Build a simple three-row comparison and fill each cell for the two smog types directly opposite each other, rather t …

Assuming both types of smog need sunlight, or both need fog -- each is defined by only …