Question

What three elements are needed to start a fire?

Answer 1

Hint: Fire is generated when a combustion reaction takes place between a fuel and oxygen on a large scale. This process releases a huge amount of energy in the form of heat and light and acts like a chain reaction if not stopped immediately.

Complete answer:
Fire is a chemical reaction in which energy in the form of heat is produced when fuels come in contact with oxygen. This process is known as Combustion.
The three elements that are needed to start a fire are oxygen, heat, and fuel. These three elements are said to be a part of the fire triangle, which is an illustration that shows the interdependence of the elements that are necessary to start and sustain a fire.

Fuels are substances that react with oxygen to release energy (exothermic). Most of the energy is released as heat, but light energy is also released. Heat is required to reach the ignition temperature of the fuel. Complete combustion of fuel needs a plentiful supply of air so that the elements in the fuel react completely with oxygen.
Complete removal of any one of the three sides or elements from the fire triangle will cease the fire. Similarly, increasing any one or more of the elements will increase the intensity of the fire.

Additional information:
The carbon dioxide extinguisher works by pushing oxygen away from the fire and replacing it with carbon dioxide, which is inflammable and denser than air.

Note:
Fire can be stopped by removal of oxygen from the area with a carbon dioxide extinguisher or a fire blanket, or by removing heat using water, which absorbs the heat from a fire very effectively. However, water should never be used on electrical fires due to the risk of electrical shock.