Questions

5 F on a H is a letter equation which indicates that 5 Fingers on a hand.

Lady of the Lamp

Carbon monoxide is a common atmospheric pollutant in the world which is produced in combustion process in automobiles and industries. It has no smell and cannot be seen.

Secondary pollutants include ozone, which is formed when hydrocarbons (HC) and nitrogen oxides (NOx) combine in the presence of sunlight.

Whereas Primary pollutant are those pollutants that are directly emitted from their sources, like CO2, CO, SO2 as these gases are directly emitted form burning of fossil fuels.

Acid rain, which is formed when sulfur dioxide or nitrogen oxides react with water, sulfuric acid etc.

Hence, Acidrain is a secondary air pollutant.