(/)
None. Since fire is not made of matter, it cannot be fitted into any physical state. Though we see and feel the flame, it is only energy. Fire catches wood, for example, when it exceeds 260 °C. At this temperature, the wood molecules are broken into atoms, which combine with the oxygen in the air and form water molecules.
The birth of H2O appears to us in the form of flames. This is because the energy that fits into the water molecules is less than that released by the wood. So what’s left of the reaction turns into light and heat – or rather, fire. There is a certain folklore regarding the supposed physical state of the flames. Non-scientific books have already pointed out that fire belongs to the fourth state of matter, plasma. Is not true. “This state occurs when a gas becomes a cloud of atomic nuclei and electrons, separated from each other”, says chemist Flávio Maron Vichi, from USP.
As these particles (nuclei and electrons) always appear together in gases, solids and liquids, plasma is considered a state apart. It usually occurs in stars at temperatures of millions of degrees Celsius.
Read too:
– What is the physical state of the glass?
– What is the fourth state of matter?
– What is nuclear fusion and fission?