Question

refer to the following characteristics of fuel

Answer 1

A fuel is any material that can be made to react with other substances so that it releases chemical or nuclear energy as heat or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but has since also been applied to other sources of heat energy such as nuclear energy (via nuclear fissionand nuclear fusion).

The heat energy released by reactions of fuels is converted into mechanical energy via a heat engine. Other times the heat itself is valued for warmth, cooking, or industrial processes, as well as the illumination that comes with combustion. Fuels are also used in the cellsof organisms in a process known as cellular respiration, where organic molecules are oxidized to release usable energy. Hydrocarbons and related oxygen-containing molecules are by far the most common source of fuel used by humans, but other substances, including radioactive metals, are also utilized.

Fuels are contrasted with other substances or devices storing potential energy, such as those that directly release electrical energy(such as batteries and capacitors) or mechanical energy (such as flywheels, springs, compressed air, or water in a reservoir).

The first known use of fuel was the combustion of wood or sticks by Homo erectus nearly two million years ago.[2][page needed] Throughout most of human history fuels derived from plants or animal fat were only used by humans. Charcoal, a wood derivative, has been used since at least 6,000 BCE for melting metals. It was only supplanted by coke, derived from coal, as European forests started to become depleted around the 18th century. Charcoal briquettes are now commonly used as a fuel for barbecue cooking.[3]

Coal was first used as a fuel around 1000 BCE in China. With the energy in the form of chemical energy that could be released through combustion,[4] but the concept development of the steam engine in the United Kingdom in 1769, coal came into more common use as a power source. Coal was later used to drive ships and locomotives. By the 19th century, gas extracted from coal was being used for street lighting in London. In the 20th and 21st centuries, the primary use of coal is to generate electricity, providing 40% of the world's electrical power supply in 2005.[5]

Fossil fuels were rapidly adopted during the Industrial Revolution, because they were more concentrated and flexible than traditional energy sources, such as water power. They have become a pivotal part of our contemporary society, with most countries in the world burning fossil fuels in order to produce power.

Currently the trend has been towards renewable fuels, such as biofuels like alcohols.

Answer 2

Characteristics of an ideal fuel:
* It should be fairly cheap and easily available.
*It should burn at a moderate rate.
* It should not produce any poisonous and irritating fumes during burning.
* It should leave no ash during burning.
*It should produce large amount of heat per unit mass i.e., it should have high calorific value .
* It should be safe and convenient from the storage and transportation point of views.
* Its ignition temperature should me above room temperature. So that it is safe to use.