You must have seen a fire, right? Well, then, you can certainly answer this question. Actually, what color is the flame? Why flames can be different? Maybe someone wants to answer yellow, orange, blue, or even black like a… um… hellfire. So, what about colorful fireworks every new year? So like our friends, are you also starting to wonder about the color of the fire?
What is a Fire?
Water, soil, fire, and air. We must have been very familiar with all four elements. For centuries, human civilizations in all corners of the world have known these four elements as–in quotation marks – “matter” constituents of the universe. Modern science proves that fire is different from others! Not because fire likes to attack other elements, but because fire is not a matter, but the effects created by the reactions of matter. Scientifically, this reaction we know as “combustion”.
For those of you who love chemistry, this is the equation you’ve been waiting for! In short, combustion will occur when the fuel is contacted with oxygen, then heated to its ignition point to react. From this reaction, water vapor and carbon dioxide form. In addition, there is also great energy in the form of heat radiation and light waves. This is what we call fire. Well, now we know about the principle of combustion reactions. But, why do we have to study like this just to know the secret behind the colors of fire?
What Determines the Color of a Fire?
The color of the fire is determined by how efficiently the combustion reaction takes place. The more efficient the combustion, the hotter the resulting temperature. And the higher the combustion temperature, the more visible the electromagnetic radiation emitted, starting from dark red to orange, to yellow, to finally bluish white. This is the first reason that generally, efficient combustion will produce blue flames, while less efficient ones will produce yellow or orange flames.
Furthermore, the efficiency of combustion is also strongly determined by the presence of oxygen. Without oxygen, there’s no hope of a fire. We’re lucky because until now, Earth has been the only planet where we can light a fire. The secret is in our Earth’s atmosphere, which is 21% oxygen. That’s why combustion also tends to be more efficient if we use gaseous fuels. The reason is that gaseous fuels mix more easily with oxygen in the air when heated. That’s why the meatballs that we cook must be cooked faster if we use a gas stove than kerosene stoves. Compared to gas, kerosene combustion is less efficient, resulting in dirty substances in the form of soot. It is the soot that emits a reddish-yellow light when heated.
By the way, gas and kerosene are both hydrocarbons, aka consisting of elements of hydrogen and carbon. Generally, hydrocarbon compounds are among the most efficient fuels because they are easily bonded to oxygen. And just so you know, these two elements will emit blue light waves when heated.
In principle, different elements can indeed emit different light as well. Because at the atomic level, the electrons get excited when they’re heated. As a result, this excitement will emit light waves that vary according to the character of the element. If you want to experiment after this, it’s okay. Just don’t be inside the house! Thanks.
