22-1-the-structure-of-the-atom_summary

The section discusses the structure of the atom, focusing on Rutherford's experiment, the emission and absorption spectra of atoms, the Bohr model, and the quantum model of the atom. By the end of the section, students should be able to: 1. Describe Rutherford's gold foil experiment and his model of the atom. 2. Describe emission and absorption spectra of atoms. 3. Describe the Bohr model of the atom. 4. Calculate the energy of electrons when they change energy levels. 5. Calculate the frequency and wavelength of emitted photons when electrons change energy levels. 6. Describe the quantum model of the atom. This section aligns with the standard (8) Science concepts, which expects students to know simple examples of atomic, nuclear, and quantum phenomena, and to compare and explain the emission spectra produced by various atoms. The gold foil experiment by Rutherford is discussed, which disproved the plum pudding model of the atom and showed that the gold nucleus is very small and contains nearly all of the gold atom's mass. Rutherford's planetary model of the atom is also discussed, which pictures low-mass electrons orbiting a large-mass nucleus. The emission and absorption spectra of atoms are explained, with an emphasis on their quantized nature, due to the quantization of energy states for electrons in an atom. The quantum model of the atom is then introduced, which explains that electrons in an atom do not exist in well-defined orbits, but instead exist in clouds of probability, due to the wave-like nature of matter. The Heisenberg uncertainty principle is also discussed, which states that it is impossible to measure a physical quantity exactly, and greater precision in measuring one quantity produces less precision in measuring a related quantity. The section emphasizes the importance of experimentation in the scientific process, and how experiments taking place today to further understand the composition of the atom could have similar effects on our understanding of atomic structure. Several simulations and activities are also provided for students to explore the concepts further.