What is alchemy?
Article three: Why we have Chemistry today and what was the difference in old and new chemistry?
The Chemistry we know today exists because of Antoine Lavoisier, Robert Boyle, and many others. The new and old chemistry are different because old chemistry was more based on alchemy, and modern chemistry is more based on materialistic things, rather than alchemy which is an more ancient belief based heavily on spiritual and mystical components.
Ouroboros
-1478 (drawing in alchemical tract)
Credits: Wikipedia
Aurora consurgens
-15th Century (Drawing of an angel foud in Aurora consurgens (treatise/book written in the 15th century))
Credits: Wikipedia
Conclusion
In conclusion, alchemy and modern chemistry are two very different things and based on very different ideas and views (alchemy is based on more spiritual and mythological ideas, whilst modern-day chemistry is based more on technology and more materialistic ideas).