Chapter 7 Flashcards
Electromagnetic Theory
If a charged particle spins on its axis it produces a magnetic field
Electron Spin Quantum Number
used to describe the direction of the electron’s spin
It can take on one of two values, +½ and -½
An experiment done by Stern and Gerlach showed that electron spin did exist
Degenerate
Have the same energy
Examples of degenerate orbitals
Anything containing same n number
Electron Configuration
Distribution of the electrons among the atomic orbitals
Orbital Diagrams
Pictorially showing where electrons are with spin of electrons
Pauli Exclsion Principle
no two electrons in an atom can have the same four quantum numbers (they can have the same values of n, l, and ml but then the values of ms must be different
Therefore, each orbital can hold only two electrons, one of each spin
Shielding Effect
Electrons gain stability through their attraction to the positively-charged nucleus
Since the n = 2 orbitals are larger than the 1s orbital, the two 1s electrons help to block or “shield” the n = 2 electrons from the attractive forces of the nucleus
Which are closer to the nucleus 2s or 2p?
2p = less penetrating, more shielded, higher energy, easier to remove, lower IE, lower z effective
Orbital Penetration
Orbitals with lower values of l are more penetrating
Hund’s Rule
most stable arrangement of electrons in subshells is the one with the greatest number of parallel spins
Diamagnetic
Repelled from a magnet
All spins are paired in outer shell
Paramagnetic
If an atom has more electrons spinning in one direction than the other, then the magnetic fields would reinforce each other and the atom would have a net magnetic moment
Who created the periodic table?
Mendeleev
Henry Moseley
Correlated frequency of xrays emitted by elements to atomic number
