At the heart of the Zettelkasten method lies the concept of “atomic notes.” These are brief, self-contained notes that focus on a single idea or concept. Unlike traditional note-taking ...

Photo: Niels Bohr's research notes for his new atomic theory Rutherford's find came from a very strange experience. Everyone at that time imagined the atom as a "plum pudding." That is ...

For example, the atomic number of sodium is 11. Every sodium atom has 11 protons and 11 electrons. It has 11 positive charges and 11 negative charges. The mass number of an atom is its total ...