1. B y: Dev Patel and Arnold Hernandez

2. Aristotle/Democritus (Ancient Philosophy)  Who- Aristotle and Democritus  When-More than 2,000 years ago  Where-Greece  What-Aristotle believed in four elements: Earth, Air, Fire, and Water. Democirtus believed that matter was made of small particles he named “atoms.”  Why-Aristotle and Democritus used observation and inference to explain the existence of everything.

3. Alchemists(Ancient Philosophy)  Who-Alchemists(European Scientist)  When-800-900 years ago  Where-Europe  What-Their work developed into what is now modern chemistry.  Why-Trying to change ordinary materials into gold

4. John Dalton(Atomic Particle Theory)  Who-John Dalton  When-1808  Where-England  What-Describe atoms as tiny particles that could not be divided. Thought each element was made of its own kind of atom. Developed the “Atomic Theory”  Why-Building on the ideas of Democritus in ancient Greece.

5. Dalton’s Atomic Theory  Elements are composed of small indivisible particles.(atoms)  Atoms of the same element are identical. Atoms of different elements are different.  Atoms of different elements combine together in simple proportions to create compounds.  In a chemical reaction, atoms are rearranged not changed.