Carbon dioxide, water vapor, oxygen, and nitrogen are the primary components of flames. If the gases reach sufficiently heated, they may become ionized and generate plasma. The color of the flame and the strength of the fire will vary depending on the items set ablaze and any contaminants outside. Flames consist of carbon particles, mostly in the form of charcoal, that give off heat when exposed to air.
Fire can be used for good or evil. It provides energy for humans to cook their food, keep them warm at night, and drive machinery. But it also causes damage to animals and plants, and can even lead to extinction if not controlled properly. The study of fire is called "fire science".
There are three main types of fires:
1. Sparking Fires Spontaneous combustion inside materials such as wood, paper, cloth, and cotton produces large amounts of heat that can cause other material nearby to burn as well. This type of fire is usually started by a spark from welding, heating, or ignition sources such as candles or cigarettes. Spontaneous combustion is how many house fires start.
2. Extinguished Fires Some materials will not burn completely without some kind of fuel present. For example, dry wood does not burn completely into its basic elements (carbon+oxygen) because there is no free hydroxyl (OH-) group available to react with the remaining oxygen to make water.
The visible component of the fire is the flame. The heat released during this process is enough to convert more gas into flames.
Carbon dioxide becomes a flammable gas when it molecules collide with each other with such force that they break apart. This happens only at very high temperatures, but even at lower temperatures carbon dioxide is still flammable because its molecules are constantly moving around, so they always have some part of their surface exposed. That's why a small amount of air is enough to fuel a CO2 fire; there will be enough oxygen present to burn all the carbon dioxide molecules before they can clump together.
Water vapor is almost entirely invisible, but it is a gas at normal temperatures. It will dissolve in liquid oxygen or hydrogen (or both) to form steam, which is what causes explosions when too much steam is produced in a confined space. Water also produces heat when it evaporates, so it plays an important role in fire behavior.
Oxygen is the most common element in the universe and one of the most common elements on earth. It is a red-colored oxidizer that exists in two forms: solid and gas.
Flames are the consequence of a chemical reaction, most notably one between oxygen in the air and a fuel such as wood or propane. The process creates carbon dioxide, steam, light, and heat in addition to other byproducts. If the flame is sufficiently hot, the gases get ionized and transform into still another state of matter: plasma. Plasma is made up of charged particles that are not only visible but also capable of hitting surfaces with enough force to leave marks.
Plasma is found in lightning bolts and volcanic eruptions but it can be created artificially by heating small amounts of substances like hydrogen or helium until they reach temperatures high enough for their molecules to break down and form ions and electrons instead. Ions are atoms with an electron missing or one too many; electrons are very small particles that orbit nuclei. Ions are the building blocks of everything that is not hydrogen or helium. They are found in nature as well as in laboratories. Ions can be positive or negative depending on how many electrons they have. For example, atoms of oxygen contain eight electrons in their outer shell but only six electrons are available because of their position next to other elements with more electrons than oxygen; this makes oxygen+ ions.
Ions are responsible for many phenomena observed in chemistry experiments and in physics courses. For example, when hydrogen gas is heated, some molecules will break away from the main body and enter into a higher energy level called an "ion" state.
"Whether a plasma occurs in a flame depends on the substance being burnt and the temperature." Of course, any ionized gas cannot be labeled a plasma because all gases have a modest degree of ionization. However, if you increase the number of electrons per molecule, then you can reach the point where the molecules are no longer neutral and become a plasma.
Fire is a complex phenomenon that involves many different processes occurring at the same time. The three main components of a flame are the oxygen, the fuel, and the heat. All materials emit light when heated to a certain temperature, but not all materials burn completely. Oxygen is used up when it joins with other substances to form compounds. Carbon is the most common element found in organic compounds such as trees and people. So, when carbon burns, only carbon monoxide and water vapor are left over after the fuel has been consumed. In fact, almost 100% of the original material is destroyed if it is oil or coal.
The color of flames results from very intense absorption of visible light by highly excited atoms and molecules. Because of this property, flames can be used as a tool for visualizing the energy levels of atoms and molecules. Fluorine has one electron in its outer shell which means it does not emit light itself, but it does absorb light very strongly.