Do you know about the Quantum Theory of Electrons in Atoms !!!!

See,

The energy levels are labeled with an n value, where n = 1, 2, 3,… So, generally speaking, the energy of an electron in atom is greater for greater values of n. This number, n, is referred to as the principle quantum number.

The principle quantum number defines the location of the energy level. It is essentially the same concept as the n in the Bohr atom description. Another name for the principal quantum number is the shell number. The shells of an atom can be thought of concentric circles radiating out from the nucleus. The electrons that belong to a specific shell are most likely to be found within the corresponding circular area. The further we proceed from the nucleus, the higher the shell number, and so the higher the energy level. The positively charged protons in the nucleus stabilize the electronic orbitals by electrostatic attraction between the positive charges of the protons and the negative charges of the electrons. So the further away the electron is from the nucleus, the greater the energy it has.

This quantum mechanical model for where electrons reside in an atom can be used to look at electronic transitions, the events when an electron moves from one energy level to another. If the transition is to a higher energy level, energy

is absorbed, and the energy change has a positive value. To obtain the amount of energy necessary for the transition to a higher energy level, a photon is absorbed by the atom. A transition to a lower energy level involves a release of

energy, and the energy change is negative. This process is accompanied by emission of a photon by the atom.

The following equation summarizes these relationships and is based on the hydrogen atom:

ΔE = E _final – E _initial

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