Quantum Numbers

• The electron is believed to be the most mysterious particle in an atom because of its location.
• According to the planetary model, there are three sub-atomic parts: proton, neutron, and electron.
• Protons have positive charge while electrons have negative charges.
• Neutrons do not carry any electrical charge.
• the location of an electron depends on the amount of energy it has.
• When an electron is low in energy, it is called a ground state.
• When an electron is high in energy, it is called an excited state.
• the highest energy level is called the valence Shell. The electrons in this level are called valence electrons.
• Valence electrons are essential in determining the chemical reactions of an atom.
• atoms with complete valence electrons tend to be stable.
• to get the maximum number of electrons in an energy level, square the energy level and multiply it by 2.
• A closed shell is when a certain shell is complete in electrons.
• An orbital is a region around the nucleus of an atom where you can find electrons.
• the different atomic orbitals are sharp (s), principle (p), diffused (d), and fundamental (f).
• the s orbital is a spherical cloud that becomes less dense as it distances from the nucleus.
• the p orbital is a dumbbell-shaped cloud with 2 lobes on opposite sides of the nucleus. It has three orientations: px, py, and pz.
• the d orbital is a four-leaf clover, an hour, and a ring orbital. There are five orbitals based on their spatial orientation.
• the f orbitals are difficult to represent visually. 7 orbitals have complex appearances.
• Electron configuration is a shorthand representation of how electrons are located within orbitals, levels, and sublevels. It describes the probability distribution of electrons around the nucleus.
• The Pauli Exclusion Principle states that an orbital can only hold up to 2 electrons of opposite spins.
• Hund's rule states that when filling a subshell, each orbital must be occupied singly before they are occupied in pairs.
• The Aufbau Principle states that The added electron will always occupy the orbital with the lowest energy first.
• Quantum Numbers are used to describe the position and energy of electrons in an orbit.
• The Principal Quantum Number denotes the average distance of the electron shell from the nucleus.
• The Azimuthal Quantum Number describes the shape of the orbital.
• The Magnetic Quantum Number describes the orientation of the electrons in space.
• The Spin Quantum Number describes the orientation of the electron spin.
• quantum numbers are integers except for spin.
• the lowest value that the principle can have is 1.
• the highest value of an Azimuthal may depend on the Principle.
• The magnetic can be any integer from -1 to +1.
• The spin can only be +1/2 and -1/2.