Quantum Numbers
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Quantum numbers are the four numbers assigned to every electron in an atom describing its location. This description is necessary for every atom because of the Pauli Exclusion Principle stating that no two electrons in an atom can be in the same type of electron probability cloud with the same spin (spin being a property of electrons I will explain momentarily) at the same time. The different quantum numbers are: The Principal Quantum Number (n), The Angular (Azimuth) Quantum Number (l), The Magnetic Quantum Number (m or ml), and The Spin Quantum Number (s or ms).
Principal Quantum Number
The principle quantum number describes the size and energy level of an electron's orbital. It also represents the shell that any given electron is in. This quantum number's value is always a natural number i.e. it is grater than or equal to 1.
The Angular Quantum Number
The angular quantum number essentially describes the shape of an electron's orbital. It can have a value greater than or equal to 0 and less than or equal to n-1. Depending on this value the suborbital for the electron is changed as well as the shape of that suborbital. Different suborbitals have different numbers of probability clouds for where electrons can be placed; this steadily increasing in along with the value of l. Since every probability cloud can contain two electrons, one with each spin (see The Spin Quantum Number), this accounts for the increasing number of electrons that progressive orbitals can hold. S Suborbital=0 Shape: Sphere, P Suborbital=1 Shape: Polar, D Suborbital=2 Shape: Cloverleaf, F Suborbital=3 Shape: Complex. For more on how this quantum number effects electron configuration, see out quantum numbers in electron configuration page. http://nuclearchem101.weebly.com/quantum-numbers-in-electron-configuration.html
The Magnetic Quantum Number
The magnetic quantum number describes the orientation in space of any given orbital of an electron. The value of the magnetic quantum number is greater than or equal to negative l and less than or equal to positive l. The magnetic quantum number determines the number of probability clouds that a particular value for l can have. A different value for m in effect changes the shape of a probability cloud that an electron can occupy.
The Spin Quantum Number
The spin quantum number is self explanatory as it describes the spin behavior of an electron in an orbital, either clockwise or counterclockwise. Although electrons do not actually spin in their orbitals, they behave as if they were spinning. Since there are only two possibilities for this quantum number it only has two possible values 1/2 or -1/2.
Where do we get that information from?
Scientists gathered the information on the different quantum numbers through experimentation on the atomic model initially and later through using the Pauli Principle to try to explain the electron's place in the atomic model. All the quantum numbers can be explained mathematically using Schrödinger's wave equations. The different numbers themselves were each discovered by different people. n was discovered by Bohr and was the first to be discovered, then the renowned Sommerfeld discovered l and m, finally Pauli himself discovered s.
Do electrons actually spin, like little planets around a nuclear sun?
In reality since electrons inhabit probabilistic clouds surrounding the nucleus. Bohr's planetary atomic model theorized that electrons behaved this was later proven wrong with the rise of quantum numbers. The orbital surrounding has a different shapes, none of which are flat circular orbits.
Principal Quantum Number
The principle quantum number describes the size and energy level of an electron's orbital. It also represents the shell that any given electron is in. This quantum number's value is always a natural number i.e. it is grater than or equal to 1.
The Angular Quantum Number
The angular quantum number essentially describes the shape of an electron's orbital. It can have a value greater than or equal to 0 and less than or equal to n-1. Depending on this value the suborbital for the electron is changed as well as the shape of that suborbital. Different suborbitals have different numbers of probability clouds for where electrons can be placed; this steadily increasing in along with the value of l. Since every probability cloud can contain two electrons, one with each spin (see The Spin Quantum Number), this accounts for the increasing number of electrons that progressive orbitals can hold. S Suborbital=0 Shape: Sphere, P Suborbital=1 Shape: Polar, D Suborbital=2 Shape: Cloverleaf, F Suborbital=3 Shape: Complex. For more on how this quantum number effects electron configuration, see out quantum numbers in electron configuration page. http://nuclearchem101.weebly.com/quantum-numbers-in-electron-configuration.html
The Magnetic Quantum Number
The magnetic quantum number describes the orientation in space of any given orbital of an electron. The value of the magnetic quantum number is greater than or equal to negative l and less than or equal to positive l. The magnetic quantum number determines the number of probability clouds that a particular value for l can have. A different value for m in effect changes the shape of a probability cloud that an electron can occupy.
The Spin Quantum Number
The spin quantum number is self explanatory as it describes the spin behavior of an electron in an orbital, either clockwise or counterclockwise. Although electrons do not actually spin in their orbitals, they behave as if they were spinning. Since there are only two possibilities for this quantum number it only has two possible values 1/2 or -1/2.
Where do we get that information from?
Scientists gathered the information on the different quantum numbers through experimentation on the atomic model initially and later through using the Pauli Principle to try to explain the electron's place in the atomic model. All the quantum numbers can be explained mathematically using Schrödinger's wave equations. The different numbers themselves were each discovered by different people. n was discovered by Bohr and was the first to be discovered, then the renowned Sommerfeld discovered l and m, finally Pauli himself discovered s.
Do electrons actually spin, like little planets around a nuclear sun?
In reality since electrons inhabit probabilistic clouds surrounding the nucleus. Bohr's planetary atomic model theorized that electrons behaved this was later proven wrong with the rise of quantum numbers. The orbital surrounding has a different shapes, none of which are flat circular orbits.