Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Air Pollution: Presence of materials in air in concentrations harmful to humans and environment. Major pollutants include , , , and particulate matter ( and ).
Electrostatic Precipitator (ESP): A device used to remove over of particulate matter from industrial exhaust. It uses electrode wires at high voltages to produce a corona that releases electrons, giving dust particles a negative charge.
Catalytic Converters: Fitted in automobiles to reduce emission of poisonous gases. They use expensive metals like platinum-palladium and rhodium as catalysts to convert unburnt hydrocarbons into and , and and nitric oxide into and gas.
Biochemical Oxygen Demand (): The amount of dissolved oxygen needed by aerobic biological organisms to break down organic material present in a given water sample. High indicates high water pollution.
Biomagnification: The increase in concentration of a toxicant (like or Mercury) at successive trophic levels. This happens because a toxic substance accumulated by an organism cannot be metabolized or excreted.
Eutrophication: Natural aging of a lake by biological enrichment of its water. 'Cultural Eutrophication' is accelerated aging due to human activities like sewage and agricultural runoff providing excess nitrogen () and phosphorus ().
Greenhouse Effect: A natural phenomenon where gases like (), (), (), and () trap heat in the Earth's atmosphere, leading to Global Warming.
Ozone Depletion: Degradation of the ozone layer in the stratosphere primarily due to Chlorofluorocarbons (). The thickness of ozone is measured in Dobson Units ().
Solid Waste Management: Categorized into bio-degradable, recyclable, and non-biodegradable. Includes E-waste (electronic waste) which is buried in landfills or incinerated.
Deforestation: Conversion of forested areas to non-forested ones. Concepts include 'Jhum cultivation' (Slash and burn) and the 'Chipko Movement' for forest conservation.
📐Formulae
💡Examples
Problem 1:
Explain the biomagnification of in an aquatic food chain starting from water with ppb.
Solution:
The concentration of increases at each trophic level: Water ( ppb) Zooplankton ( ppm) Small fish ( ppm) Large fish ( ppm) Fish-eating birds ( ppm).
Explanation:
Because is lipophilic and not easily metabolized, its concentration increases nearly times from water to the top predator, interfering with calcium metabolism in birds and causing eggshell thinning.
Problem 2:
In a water body, the is found to be mg/L. What does this indicate about the water quality and the level of Dissolved Oxygen ()?
Solution:
A of mg/L indicates highly polluted water (likely raw sewage) and very low levels of Dissolved Oxygen ().
Explanation:
There is an inverse relationship: as sewage/organic matter increases, increases because microbes consume to decompose the waste, leading to a sharp decline in , which often causes the death of fish and other aquatic creatures.