Chapter 4: Modern Atomic Theory

key advances made by the quantum theory model of the atoms

basically discovery of orbitals

orbital

an electron cloud where the electron could be anywhere in that cloud

Orbit

a place where the electron def is like it's there no question about it and it cannot move around it can only go from one orbit to another

how many electrons can be in each atomic orbital

2

total electron capacity of s

2

total electron capacity of p

6

total electron capacity of d

10

total electron capacity of f

14

Aufbau Principle

in the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels (e.g., 1s before 2s). In this way, the electrons of an atom or ion form the most stable electron configuration possible

Pauli Exclusion Principle

An orbital can only hold 2 electrons which must have opposite charges

Hund's Rule

every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.

ionization energy

The amount of energy required to remove the most loosely bound electron, the valence electron.

periodic trends for atomic size

Increase

|

|

|

------------> v

decrease

periodic trends for ionization energy

decrease

|

|

|

------------> v

Increase

Octet Rule

Elements react to form compounds in such a way as to put 8 electrons in their outermost valence shell-shell configuration identical to that of a noble gas and making them exceptionally stable

Uncertainty Principle

In dealing with particles the size of an electron it is impossible to know with any real accuracy exactly where the electron is or where it's going

What gave schrodinger justification to think of an electron in an atom as a nebulous cloud

Heisenberg's uncertainty principle, by stating that it is impossible to exactly locate an electron.

If an electron couldn't be exactly located in a volume of space, Schrödinger reasoned,

it could be thought of as being everywhere in that volume at once, filling it like a cloud.