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Bohr's circles work for hydrogen, and they fail for every other atom. The better picture is a cloud of probability. In this course we meet the waves of matter, the uncertainty principle, the four quantum numbers and the shapes of orbitals. Then we use three rules to write the electron configuration of any atom, and we explain the odd cases, such as chromium and copper.
Why can an electron in an atom never be at rest? Why does oxygen lose an electron more easily than nitrogen, although its nucleus pulls harder? In this course we read two ideas that the main chapter only touches: the electron in a box, and the shielding of the nucleus by the inner electrons. Then we solve harder problems at the level of JEE Advanced, AP Chemistry and A-Level Chemistry, and take an advanced timed test.