Chemistry now depends on empirical data rather than mere reasoning.
Explanation:
Modern chemistry is considered scientific because it depends on the scientific method.
Science is empirical in nature. Hypothesis are confirmed based on careful observation and experimentation before inferences are made based on experimental observations.
Chemistry in ancient times was based mostly on thought and reasoning. A typical example is the phlogiston theory which had no experimental backup.
Today chemistry entirely depends on evidences which are reproducible rather than mere reasoning.
