Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Waste is any material that is no longer useful and is thrown away. It is classified into two types: Biodegradable and Non-biodegradable.
Biodegradable waste includes organic matter like food peels and paper that can be broken down by microorganisms into simpler substances like , , and compost.
Non-biodegradable waste includes materials like plastic (polymers like ), glass, and metal that do not rot and remain in the environment for hundreds of years.
The 3Rs Principle: Reduce (use less), Reuse (use items multiple times), and Recycle (process old materials to make new ones).
Composting is a method where organic waste is buried in a pit to turn into manure. This process requires moisture () and oxygen () for aerobic bacteria to work.
Waste Segregation: Green bins are used for 'wet waste' (biodegradable), and Blue bins are used for 'dry waste' (recyclable non-biodegradable items).
Landfills are large open areas outside cities where non-recyclable waste is dumped and covered with soil to prevent the release of harmful gases like (Methane).
📐Formulae
💡Examples
Problem 1:
A school generates kg of waste daily. If of this waste is biodegradable and can be composted, how many kilograms of waste will go to the landfill every day?
Solution:
Waste for landfill = .
Explanation:
By separating of biodegradable waste for composting, we only send the remaining (non-biodegradable/non-recyclable) to the landfill.
Problem 2:
Identify the gas represented by that is released when dry leaves are burnt, and explain why composting is better than burning.
Solution:
is Carbon Dioxide. Composting is better because burning releases and smoke which causes air pollution, whereas composting turns waste into nutrient-rich manure.
Explanation:
Burning organic matter increases the concentration of in the atmosphere, contributing to global warming, while composting recycles nutrients back into the soil.