Formation of Atoms
Along with protons and neutrons, there are another type of fundamental particles called, Electrons. Electrons are the lightest of charged leptons
When electrons and atomic nuclei bind together, they form atoms: building blocks of normal matter that makes up everything in our day to day experience.
Before humans even recognized how atoms were structured, we had determined many of their properties.
In the 19th century, we discovered that the electric charge of the nucleus determined an atom’s chemical properties, and found out that every atom had its own unique set of spectral lines that it could emit and absorb.
Experimentally, the evidence for a discrete, quantum Universe was known long before theorists put it all together.
In 1912, Niels Bohr proposed his now famous model of atom, where electrons orbited around atomic nucleus like planets orbited Sun.
The big difference between Bohr’s model and our Solar System though, was that there were only certain particular states that were allowed for an atom, whereas planets could orbit with any combination of speed and radius that led to a stable orbit.
Bohr realized that the electron and nucleus were both very small, had opposite charges and knew that nucleus had practically all of the mass.
His ground-breaking contribution was understanding that electrons can only occupy certain energy levels which he termed, “Atomic Orbitals”.
What is the Fine Structure of Atoms?