Semester I Exam Review NEW Flashcard

Dalton

 

Matter is composed of small indivisible particles called ATOMS (Billiard ball model). These particles always combined in whole number ratios.

 

Mendeleev

 

1st periodic table arrangement in “grid” format.
Arrangement was by WEIGHT.

[image]

Bunsen

 
Inventor of the SPECTROSCOPE.  Identified 3 types of spectra:  Continuous, Emission (or bright line), and absorption.
 
[image] 

Thomson

 

Used a highly modified cathode ray tube to discover the ELECTRON.  (see diagram below)

Measured the RATIO of mass to charge in an electron.

[image]

Rutherford


Gold foil experiment. First to experiment on the structure of the atom.

[image]

A = Hard impenetrable center called the nucleus.
B = Atom is mostly empty space
C = Nucleus has a (+) charge, same as an alpha particle

Bohr

 

Added the concept of 7 ENERGY LEVELS to the Rutherford solar system model of the atom. Also explained Bright-line & absorbtion spectra by electrons changing energy levels as atoms absorb and emit light energy.

[image]

Heisenberg

Uncertainity Principle. The exact position of an electron cannot be known all the time, due to the electron size and speed. Beginnings of the statistical model of the atom. 

 

 Also was leader of the Nazi project to construct an atomic weapon during WWII.

Shroedinger

Developed the statistical model of the atom to include areas of high electron probability called ORBITALS.

 

 

 

[image] 

 

Pauli
Exclusion principle (2 electrons maximum per orbital shape…) and the concept of electron spin or full -vs- partial orbitals.
Millikan
OIL DROP EXPERIMENT: which measured the values for the mass and charge of the electron.

[image]

Hund

Hund’s Rule:  Orbitals are created before they are filled…

 

 

 

[image]

Thomson
Pudding Cake” or “Raisin Bun” model of the atom.  The atoms were solid, but had electrons embedded in them (like fruit in a fruit-cake).
Mosley

Rearranged the modern Periodic Table based on the element’s atomic number.

 

 

[image]

Einstein

Photoelectric effect experiment proving light could act as a particle (1st solar cell)

 

 

[image]

Get instant access to
all materials

Become a Member