Early Models of the Atom –An atom is the smallest particle of an element that retains its identity in a chemical reaction. –Philosophers and scientists.
© Copyright Pearson Prentice Hall Slide 1 of 18 Tuesday!!!!! 10/18/11 Bell Ringer 1. Pick up your papers from the corner desk. 2. Get out paper to take.
Atomic Structure and the Periodic Table Early Models of the Atom Dalton’s Atomic Theory - All elements are composed of atoms - All elements are composed.
Atomic Structure History of Atomic Theory. Democritus (460 - 370 BC) Was the first person to come up with the idea of atom Believed that all matter was.
Slide 1 of 18 Chemistry 4.1. Slide 2 of 18 © Copyright Pearson Prentice Hall Defining the Atom > Early Models of the Atom An atom is the smallest particle.