wagner chem lesson 2

Aufbau Principle

Aufbau Principle

An electron occupies the lowest-energy orbital one at a time

atomic theory explains?

how chemical reactions occur

exited state

electrons jump to high energy orbitals

The center of an atom contains most of the mass and is positively charged the electrons move in the case empty space around the nucleus

Rutherford's model

electrons have orbits around the nucleolus each orbit has a cerein energy level.

the bohr model

neutral atoms

same number of neutrons and protons

same number of protons and neutrons

isotopes

cations and anions

cat=positive an=negative

Pauli Principle

orbitals can hold two electrons with opposite spins

hund's rule

electrons don't pair until each of the lowest energy orbitals are full

ground state

electrons jump down to lower energy orbitals

Greek philosopher with an idea, no experimental proof.

Democritus

Atoms are little solid spheres

Daltons model

positive and negative charges inside the atom

Thompsons model

number at top

atomic number (number of protons)

ions

charged atoms