Unit 03: Early Atomic Theory

Enduring Understandings:

1. The chemical elements are fundamental building blocks of matter, and all matter can be understood in terms of arrangements of atoms. These atoms retain their identity in chemical reactions.

2. Chemical and physical properties of matter can be explained by the structure and the arrangements of atoms, ions, or molecules and the forces between them.

3. Lab activities apply the process of scientific investigation, and must be safely conducted, communicated, and evaluated.

Essential Questions:

1. What is an atom?

2. Why did the model of the atom change over time?

3. What makes atoms different?

Vocabulary:

Atomic Mass

Atomic Number

Isotope

Law of Constant Composition/Law of Definite Proportions

Law of Conservation of Mass

Mass Number

Nucleus

Proton

Neutron

Electron