Question

Of the following metals which one pollutes the air of a big city?
A. Copper
B. Chromium
C. Lead
D. Cadmium

Answer 1

Hint: The air of the big cities is mainly polluted from the vehicle emissions and industrial emissions. Lead is a very harmful pollutant releases from the vehicles. Copper pollutants are mainly found in water. Chromium spread from coal and oil combustion. Cadmium enters into air through ground.

Complete answer:
The pollutants are the harmful substances present in the air. Pollutants include copper, cadmium, chromium and lead particles depending on their source of emission. The amount of copper may increase into the environment through mining, farming, manufacturing operations, and municipal or industrial wastewater released into rivers and lakes.
Toxic industrial and environmental pollutants have a high level of cadmium which is considered as human carcinogen. It is naturally found in earth’s crust. The coal and oil combustion increases the chromium concentration in the atmospheric emissions. The naturally occurring metal in the environment is lead. It is also used in manufactured products. The fuels used in on-road vehicles such as cars and trucks and industrial sources have major sources of lead emissions. In the past, motor vehicles contributed the most in the lead emissions to the air. The leaded aviation gasoline is used in ore and metals processing and piston-engine aircraft operating. The lead smelters have the highest lead concentrations. Some of the other lead emitters are waste incinerators, utilities, and lead-acid battery manufacturers.
From the above information we have found that lead pollutes the air of a big city.

Hence, the correct answer is option (C).

Note: Contamination of well water increases the level of copper in the drinking water. The corrosion of water pipes makes the water acidic. Toxicity of the chromium targets the respiratory tract. Cadmium is also found in combination with zinc. Lead has many applications as it is widely used for car batteries, pigments, ammunition, cable sheath, weights for lifting, radiation protection, etc.