Coal

Coal is a combustible black or brownish-black sedimentary rock formed from the remains of ancient vegetation which has been subjected to intense heat and pressure over millions of years. It is a readily combustible rock containing more than 50% by weight of carbonaceous material.

Formation of Coal

Coal is formed from the remains of plants and trees that lived and died millions of years ago. These plant remains were buried under layers of mud and rock. Over time, heat and pressure from the layers above caused the plant remains to change into coal.

Types of Coal

There are four main types of coal:

1. Anthracite: This is the highest quality coal, with a high carbon content and few impurities. It is often referred to as "hard coal" and is used for heating and generating electricity.
2. Bituminous: This is the most abundant type of coal. It is a middle rank coal with a high heat value and is used to generate electricity and to produce coke for steel production.
3. Subbituminous: This type of coal has a lower heating value than bituminous coal and is used primarily for electricity generation.
4. Lignite: Lignite is the lowest rank of coal and has the lowest energy content. It is mainly used for electricity generation and in industrial processes.

Uses of Coal

Coal has been used as an energy source for centuries and is still widely used for electricity generation, heating, and industrial processes. It is also used to produce coke, a crucial ingredient in the steelmaking process. However, coal combustion releases carbon dioxide and other pollutants into the atmosphere, contributing to air pollution and climate change.

Environmental Impact

The burning of coal releases various pollutants such as sulfur dioxide, nitrogen oxides, and particulate matter, which can have detrimental effects on human health and the environment. Mining for coal can also have significant environmental impacts, including habitat destruction, soil and water pollution, and landscape scarring.

Study Guide

1. What are the main types of coal and their uses?
2. How is coal formed and where is it found?
3. What are the environmental impacts of coal mining and combustion?
4. Explain the process of coal combustion and its contribution to air pollution.
5. Discuss the role of coal in the global energy landscape and the potential alternatives to coal as an energy source.

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