Bai Hong fell into deep thought. In fact, there were very few people in human society who had begun studying reaction formulas. This was only possible after one had a considerable understanding of alchemy.
In reality, other than the Alchemy King who was high and mighty, there were only a few great alchemists within human society. More or less, they had also begun to study reaction formulas.
Therefore, in his opinion, Chu Yunfan should be the disciple of one of those people. Only then could he possibly know about reaction formulas.
As for Chu Yunfan's own research, Bai Hong did not believe it at all. His age was obvious.
Someone like his granddaughter, Bai Ling'er, was already a genius. And she had only just become an advanced alchemy apprentice.