Explain how are vehicles a source of air pollution.

Vehicles cause air pollution in the following ways-

1. Vehicles account for most of the carbon dioxide, carbon monoxide, and a large share of the hydrocarbons, nitrogen oxides and particulates found in the atmosphere in major urban areas.
2. Nitrogen oxide is formed when nitrogen in the fuel or nitrogen of air heats to temperatures above 1200°F in the presence of oxygen. This reaction occurs in most car engines today.
3. Nitrogen oxides combine with water leading to a component of atmospheric acidification, specially nitric acid. This leads to acid rain.
4. Most big cities of India are affected by air pollution caused by high levels of total suspended particulates, carbon dioxide, sulphur dioxide and nitrogen dioxide. It is exhaust pollution from vehicle emissions.