Atomic Structure
Learning Objectives
- Students will be able to identify the three main subatomic particles and their properties
- Students will be able to explain the structure of an atom using the Bohr model
- Students will be able to calculate atomic number, mass number, and electron distribution
Core Concepts
- proton
- neutron
- electron
- nucleus
- electron_shell
- atomic_number
- mass_number
Formulas
$$A = Z + N$$
The total number of nucleons in an atom's nucleus
$$Z = \text{number of protons}$$
Determines which element an atom is
Units
| atomic mass unit | u or amu |
| picometer | pm |
Interesting Fact
If an atom were the size of a football stadium, the nucleus would be about the size of a marble
Key Scientist
J.J. Thomson
Discovered the electron in 1897
Philosophy
The atomic nucleus at the heart of existence suggests underlying structure; the emptiness of atoms raises questions about the nature of matter and substance.
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