Is the mass of wood charcoal and oxygen the same before and after the fire ?

Here u go I even looked it up for u ;)

The law of conservation of mass was created in 1789 by a French chemist, Antoine Lavoisier. ... For example, when wood burns, the mass of the soot, ashes, and gases, equals the original mass of the charcoal and the oxygen when it first reacted. So the mass of the product equals the mass of the reactant

hey, what do you need . just post the question and i may be able to you : )