Question: When each value of n is given, what are the possible values for l?
- The relationship between the quantum number (n) and the angular momentum quantum number (l).
- The principle quantum number is an integer that determines the overall size and energy of an orbital. The possible values for n are 1, 2, 3, … and so on.
- The angular momentum quantum number is an integer that determines the shape of the orbital. Every value of n has a certain l value. In other words, for a given value of n, l can be any integer up to n-1.
If n=3, what are the possible values of l?
Since l = n-1, and n=3. Substitute 3 with n (l=3-1), which l equals to 2 maximum values or 0, 1, 2.
- n= 2
l= 0, 1
- n= 4
l= 0, 1, 2, 3
- n= 6
l= 0, 1, 2, 3, 4, 5
- n= 8
l= 0, 1, 2, 3, 4, 5, 6, 7
Question: The formula CH4 is a tetrahedral geometry. How many electron groups are on the central atom?
- Valence Shell Electron Pair Repulsion (VSEPR) theory is based on the idea that electrons groups--- defined as lone pairs, single bonds, multiple bond, and single bonds--- repel one another.
- The repulsion between the electron groups determines the geometry of the molecule.
- The molecules that have one central atom molecular geometry depend on:
- The number of electron groups around the central atom.
- However many of those electron groups are bonding groups and how many are lone pairs.
The formula CH4 is a tetrahedral geometry with four bonded pairs with no lone pairs, so there are four electron groups.