Short answers, pulled from the story.
Robert Boyle's The Sceptical Chymist was published on the 1st of January 1661. This publication fundamentally altered how humanity understands the building blocks of reality by dismantling the ancient belief that fire, air, earth, and water were the sole constituents of the universe.
The 4th century Greek-Egyptian Zosimos of Panopolis is credited with writing the earliest known alchemical texts. These texts detail the processes of distillation and the properties of various substances that remain staples of modern chemistry.
John Dalton proposed the modern theory of atoms in 1803. This theory suggested that all substances are composed of indivisible particles called atoms, each with a specific weight, providing a framework for understanding chemical reactions.
Antoine Lavoisier established the law of conservation of mass in the late 18th century. He is often called the father of modern chemistry and demonstrated that matter is neither created nor destroyed in chemical reactions.
Dmitri Mendeleev developed the periodic table in the 1860s. He arranged the known elements by atomic weight and predicted the existence of several undiscovered elements, which later fit perfectly into the gaps he had left.