1.13 - Atomic orbitals and electronic configurations Flashcards
What are all electrons arranged in?
Quantum shells
What do all electrons in the same quantum shell have?
Similar, but not identical, energies
What do electrons in the first quantum shell have?
The lowest energy for that element
What is each quantum shell divided into?
Sub shells
What is the only subshell in the first quantum shell?
The 1s subshell
What subshells does the second quantum shell contain?
The 2s and 2p subshells
What subshells does the third quantum shell contain?
The 3s, 3p and 3d subshells
What subshells does the fourth quantum shell contain?
The 4s, 4p, 4d and 4f subshells
Order the following subshells in order of energy level, from lowest to highest: 1s 2s 2p 3s 3p 3d 4s
1s, 2s, 2p, 3s, 3p, 4s, 3d
What does each subshells contain?
Orbitals
What shape is an 1s orbital?
Spherical
How many orbitals does the 2p subshell contain?
3
What shape is each orbital in the 2p subshell?
An elongated dumbbell shape
How many orbitals does the 3d subshell contain?
5
How many electrons can an s subshell contain?
2 (1*2)
How many electrons can a p subshell contain?
6 (3*2)
How many electrons can a d subshell contain?
10 (5*2)
How many electrons can an f subshell contain?
14 (7*2)
What is the equation for finding the maximum amount of electrons in a quantum shell?
2n^2, where n is the number of the shell.
e.g. The second quantum shell can contain 2*2^2 = 8 electrons
What is the notation for a subshell, for example the 2p subshell?
2p^n, where n is the number of electrons held within this subshell
What is strange about the 3d and 4s subshells when it comes to electronic configuration of atoms that use these shells?
The 4s subshell has a slightly lower energy level than the 3d subshell, which means that it fills before the 3d subshell does
What does Hund’s rule state?
That electrons will occupy the orbitals singly before pairing takes place
What does The Pauli Exclusion Principle state?
That two electrons cannot occupy the same orbital unless they have opposite spins
What is interesting about the electronic configuration of Chromium?
It is 1s^2 2s^2 2p^6 3s^2 3p^6 3d^5 4s^1
This is strange because the 3d and 4s subshells both half-filled, instead of the 4s subshell filling completely like we would expect. This is because having the 3d and 4s subshells half-filled is more stable than having the 4s subshell completely filled, and the 3d subshell with 4 electrons in it
