## Electron Affinity

In the previous post, we talked about ionization energy which is the amount of energy required to remove an electron from the isolated neutral atom in the gaseous state.     During the ionization, a neutral atom was becoming a … Read more

## Ionization energy

When discussing the Bohr’s model of the hydrogen atom, we saw that absorbing light with sufficient energy moves the electron to a higher energy level, and when it falls back to a lower energy level, light is emitted as energy is lost.     Next, … Read more

## Calculating The Energy of a Photon

The energy of a photon, which is the energy of the light, can be calculated using the following two formulas:     The second formula is derived from the first by using the relationship between the frequency (ν), wavelength (λ), … Read more

## Photoelectric Effect

Energy and Atomic Structure Remember, when discussing the Bohr’s model for the hydrogen atom, we saw that there are orbits with distinct energies that the electron can occupy. Each orbit has its own constant radius which is directly related to … Read more

## Hund’s Rule

Hund’s rule states that electrons will fill all the degenerate orbitals (equal in energy) with parallel spins (both arrows up or down) first before pairing up in one orbital. We can also formulate it as the lowest energy configuration for an atom is the … Read more

## Pauli Exclusion Principle

The Pauli’s exclusion principle states that no two electrons in an atom can have the same four quantum numbers. Now, what does this practically mean? Essentially, the implication of Pauli’s exclusion principle is that when two electrons are in the same orbital, they must have … Read more

## Rydberg Formula

Rydberg formula is used for calculating the wavelength or the energy of the light emitted during electron transitions. So, first, what are the electron transitions, and how are they associated with light? The first thing you need to know here … Read more

## Quantum Numbers

Quantum numbers tell us the energy level, the number and the type of orbitals, and the spin of the electron. Collectively, they all describe the electron configurations. There are four quantum numbers that we are going to discuss: The Principal … Read more

## s, p, d, f Atomic Orbitals

In today’s post, we will talk about the atomic orbitals. So, first, what is an orbital? In a formal, quantum mechanical definition, orbitals are essentially probability distribution maps for electrons within atoms. In a simpler version, think of orbitals as … Read more

## Aufbau’s Principle, Hund’s Rule, and Pauli’s Exclusion Principle

Aufbau’s Principle, Hund’s Rule, and Pauli’s Exclusion Principle are rules for writing electron configurations, so go over the main principles of electron configurations if you need to before we start discussing them. Aufbau’s Principle Aufbau (German aufbauen, “to build up”) … Read more