What are Some Different Types of Flame?
The two primary types of flame are diffusion flame, in which oxidizer and fuel diffuse into one another gradually, and premixed flame, in which the oxidizer and fuel are premixed and the flame is shorter and hotter. Diffusion flames, like those in candles and forest fires, are primarily red or red/orange reflecting the blackbody emissions of heated soot particles, while premixed flames have a closely reflecting the emissions spectrum of the substance being burned, which ranges from yellow to green. Flames result from exothermic chemical reactions, that is, reactions with a net heat output. Chemical reactions that absorb heat are called endothermic. Flame occurs when a fuel and oxidizer, usually air or oxygen, mix together in the presence of sufficient heat. Our ancestors have been exploiting the heat of flame for warmth and cooking since between 1 and 1.8 million years ago. Significant transitions in history, such as the transition between the Stone Age and Bronze Age, have been determ
