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Section 10: Conclusion
Figure 3-18. The Progression of the Models of the Atom
A progression of the models of the atom over time from Dalton to quantum with the major characteristics labeled.
© Science Media Group.
To summarize, the quantum model of the atom is a culmination of many experiments by many diligent physicists, chemists, and mathematicians. The atom has a nucleus, which is a dense area of positive charge, surrounded by mostly empty space with electrons. The dense nucleus is made of protons and neutrons, and the electrons are in orbitals, which represent probable locations based on energy. The orbitals are also known as the electron clouds. Electrons changing energy levels is what produces unique colors and distinct emission spectra.
Above is a summary diagram of scientists' vision of the atom over time. The atom and its subatomic particles were steadily unveiled as researchers realized how to manipulate spectroscopic techniques.