The liberation of heat, light and aliquot substance from molecular mass. Flame or fire is a partial molecular dissociation to atomic and etheric entropic states. The flame of fire is a combination of different plasmas or what used to be called ether. Flame is plasma (gases) of differing tenuities. It's light is the emission of photons. Flame simultaneously takes in (molecular and atomic matter) and throws off (gas, plasma, light and heat). Therefore "burning" is molecular dissociation to smaller aliquot parts.