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Antoine Lavoiser
Antoine Lavoiser is a french chemist. He became known as the Father of Modern Science. He established the Law of Conservation of Mass. -
John Dalton
John Dalton developed the first useful atomic theory of matter around 1803. Dalton combined his theories in his " New System of Chemincal Philosphy " around 1808-1827. -
Law of Conservation of Mass
States that mass is neither created or destroyed in any ordinary chemical reaction. Antoine Lavoisier's discovered the Law of Conservation of Mass in 1789. -
Daltons Atomic Theory
The atomic theory is composed into five different parts.
1. Elements are composed of extremely small particles called atoms.
2. Atoms of a element are identical in size, mass, and other properties. Also atoms of different elements are different.
3. Atoms cannot be created or destroyed.
4. Atoms of different compounds combine.
5. In chemical reactions atoms are combined, separated, or rearranged. -
Dmitri Mendeleev
Dmitri worked on the periodic law. In 1871 he figured out that three knew elements exist and he was the only scientist to know that. The three new elemts he found were ekaboron, ekaaluminium, and ekasilicon. -
J.J. Thomson
Thomson discovered the electon. His early intrest in atomic structure was also reflected in his " Treatise on the motion of Vortex Ring." which later won him the Adams Prize in 1884. -
Robert Millikan
Discovered the electron change. Robert started his work on electron charge in 1906 and continued for seven years. -
Niels Bohr
Bohr intoduced a new theory on the structure of the atom in 1913. Bohr stated that electrons travel in fixed orbits around the atom's nucleus, Bohr won the Nobel Prize in Physics in 1922. -
Henry Moseley
Was a British Chemist. He developed the X-Ray spectra to study the atomic structure. He also discovered a better way to arrange the elememnts on a periodic table. -
James Chadwick
Proved that the existance of neutrons, the elementary particles without any electrical charge and a fundamental of the atoms nucleus. Chadwick won the Noble Proze in Physics in 1935 for effectively solving the jigsaw puzzle of the atom. -
Cathode Ray Tube
Also became known as an " Electron Gun " It doesn't travel in straight lines, it travels in waves. The waves carry a negative charge. -
Electron Cloud Model
Is a model where the electrons are no longer known as particles moving around the nucleus. It is also known as the " quantum mechanically-influenced model " -
Plum Pudding Model
Each atom was a sphere filled with a positively charged fluid. The model is composed of electrons surrounded by positive charge to balance the negative charges. -
Ernerst Rutherford
Rutherford created the Gold Foil Experement. He also predicted that neutrons do exist. -
Gold Foil Experiment
Consisted of a series of tests. Which positive charges were sent through a layer of gold foil. Which led to the discovery of the atomic nucleus, the planetary model of the atom, -
Rutherford Model
The model is basically like the sun and the plants surrounding the sun. In the center is the positively charged nucleus ( or also knows as the sun ) then it is surrounded by electrons in a path going around the nucleus. They rotate around in a direct path for hours. -
Bohrs Planetary Model
In 1913 Bohr published a theory about the structure of the atom. Bohr stated that electrons travel only in certain successively larger orbits.He suggested that the outter orbit could hold more then the inner orbit and that the outter orbit determains the chemical properties. -
Quantum Mechanical Model
in the Quantum Mechanical Model electrons are known as " standing waves " The model is important now because it defines the electrons movement with relationship to the nucleus. -
Erwin Schrodinger
He determined the probability location of electrons in atoms. Erwin won the Nobel Prize for Physics in 1933, for his 1926 introduction of Schrodinger's wave.
