Atoms and the Periodic Table 1.2 Flashcards
What are Quantum Numbers
They tell us where an electron is in an atom
What are the 4 quantum numbers
- Principle quantum number (n)
- Angular momentum number (l)
- Magnetic quantum number (m)
- ## Spin magnetic quantum number (+1/2 or -1/2)
What is the atomic orbital
Volume in a space where the probability of finding an electron is more than 90%
What is the principle quantum number
Determines the main energy level. It can have values n=1,2,3,4… The numbers determine the size and energy of the shell
What is the angular momentum quantum number
Determines the shape of the sub-shell and is labelled s, p, d, f.
What is the magnetic quantum number
Relates to the orientation in space of the orbital, m=-l to +l
What is the spin magnetic quantum number
Determines the direction of the spin. It can have values of +1/2 or -1/2
What is the Pauli Exclusion Principle
An orbital can hold at most 2 electrons and the electrons in that orbital must have opposite spins
What is the Aufbaus Principle
Electrons fill atomic orbitals in order of increasing energy
What is the Hunds Rule
Electrons will occupy degenerate orbitals singly and with parallel spins before pairing (think of a bus)
What does degenerate mean
Equal energy
What is the statement about stability
There is a special stability associated with having an exactly half full electronic sub shell