This man found that "respirable air" could be turned into "fixed air" through respiration or combustion. He proposed that oxygen is the source of acidity, and called another component of air "azote." He showed that oxygen and hydrogen combine to form water. In his 1789 Elementary Treatise on Chemistry, he demonstrated that weight changes during combustion were a result of 
This man found that "respirable air" could be turned into "fixed air" through respiration or combustion. He proposed that oxygen is the source of acidity, and called another component of air "azote." He showed that oxygen and hydrogen combine to form water. In his 1789 Elementary Treatise on Chemistry, he demonstrated that weight changes during combustion were a result of combining with oxygen, and not because of negative-mass phlogiston. For 10 points, name this "father of modern chemistry" who first stated the law of conservation of mass.
This man found that "respirable air" could be turned into "fixed air" through respiration or combustion.
Antoine-Laurent de {Lavoisier}