Honors Chem Chapter two unit test

Dalton

• First true atomic theory

• Billiard ball -WRONG= Atom is NOT indivisible, it is made up of protons+neutrons etc... (subatomic particles)

Thomson

• cathode ray -plum pudding -discovered electrons

Rutherford

-Gold foil -nuclear model -atom is mostly empty space, positive nucleus Nucleus=dense electron cloud=volume

Bohr

-planetary model -Studied hot hydrogen atoms and determined that the energy was "quantized"

Isotopes

Atoms of the same element that have different numbers of neutrons

Ions

positively and negatively charged atoms as a result of a change in # of electrons

photon

a particle/wave of light

When does the electron absorb energy?

when they move from lower---> higher energy levels, acted upon by a photon

When does the electron release energy? (emission)

-when they move from higher---> lower energy levels, release energy in the form of light (ground state)

paramagnetic

has unpaired electrons

diamagnetic

no unpaired electrons

how many electrons fit in each sublevel?

S=

2

how many electrons fit in each sublevel?

P=

6

how many electrons fit in each sublevel?

d=

10

how many electrons fit in each sublevel?

f=

14

Chromium

takes the electron from 4s^2 and gives it to 3d^4 to make it 3d^5

1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^5

Copper

takes the electron from 4s^2 and gives it to 3d^9 to make it 3d^10

1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^10

Aufbau Principle

the rule that electrons occupy the orbitals of lowest energy first

Pauli Exclusion Principle

An atomic orbital may describe at most two electrons, each with opposite spin direction

Hund's Rule

states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals

High energy= ______ wavelength, ______ frequency

short wavelength, high frequency

Low energy= ___ wavelength, ___ frequency

long wavelength, low frequency

The # of protons = the # of __________________________ in a neutral atom

electrons

charge and mass of electron

-1, 0.0005

charge and mass of a proton

Charge = +1 Mass = 1

charge and mass of neutron

Charge = 0 Mass = 1

electromagnetic spectrum

All of the frequencies or wavelengths of electromagnetic radiation