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John Dalton
In 1803 dalton worked tirelessly form his experiments and eventually discovered that when he put oxygen atoms next to hydrogen atoms, one oxygen would pair with two hydrogen and from water. These experiments eventually lead him to create the atomic theory through the study of gasses. The impact of daltons finding lead other scientists to study more and eventually, through trial and error create what we believe now. -
John Dalton
Daltons atomic theory consists of 3 topics, elements consist of atoms, all atoms in the same element are the same, and atoms cant be created or destroyed. -
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Dmitri Mendeleev
Mendeleev was a Russian Chemist who discovered the periodic law and was a main contributor to the early Periodic table and its organization. He was one of the founders of the Russian Chemical Society Mendeleev wrote 400+ books and articles that expanded the field of chemistry including: Organic Chemistry, The Principles of Chemistry, The Principles of Chemistry V2, and The Relation between the Properties and Atomic Weights of the Elements. -
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J. J. Thompson
On April 30, 1897 Thompson was experimenting with a cathode ray tube and he noticed that some of the beams he shot out went up rather than down, but what was weird is that gravity pulls the particles down. Heconcluded that there was another force acting on the particles, he called them electrons. He devised that because the electrons had a greater pull on the negative side of the magnet that they were negatively charged. -
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Robert Millikan
Robert Millikan is an American scientist who discovered how to measure the charge of an atom. He discovered this through an experiment with an oil drop experiment. This oil drop experiment is an experiment where he sprayed an oil mist into a tube and as they were falling they were pushed into a tunnel with two metal sides with an electric current traveling through the tunnel, when the droplets of oil came into the tunnel they would be pulled to one side, -
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Ernest Rutherford
the year 1909 Ernest Rutherford was performing an experiment with a price of gold foil and a alpha particle laser. In this experiment Rutherford shot thousands of alpha particles at the piece of gold foil, after awhile he noticed that a few alpha particles bounced back rather than going through it like 99% of the other particles. -
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Albert Einstein
Einstein was a German/Swiss theoretical physicist and mathemetician who was responsible for the “special and general theories of relativity”. Einstein produced numerous researches including his “Special Theory of Relativity (1905), Relativity (English translations, 1920 and 1950), General Theory of Relativity (1916), Investigations on Theory of Brownian Movement (1926), and The Evolution of Physics (1938).” -
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Neil’s Bohr
Niels Bohr was the one who modernized what the atom looked like with his model. He named this Bohr's model and it consists of one center which is the nucleus which had the proton and neutron found on it, then he added rings for each level of electrons. The first layer has 2 electrons then the next has 6 then 8. Each electron was repressed with a dot on the ring. This accurately represented the way the atom was made up and the count of each particle in the atom. -
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Erwin Schrodinger
Erwin Schrodinger was an Irish/Austrian physicist + philosopher who contributed to the fields of Wave theory and Quantum mechanics.
Although it is complicated to understand, simply put, Schrodinger’s Wave Equation which he discovered in 1926 describes “the energy and location” of an electron within the atom. Schrodinger founded his work on his mastery of -
Dmitri Mendeleev
Mendeleev predicted the existence of 8 additional elements to the 63-element periodic table of the time, as well as describe their properties + correlations between the elements regarding their atomic mass. He produced many theories and ideas- many were breakthroughs in the field. His work helped categorize the elements+atoms. -
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Louis De Broglie
De Broglie was a French physicist who made “groundbreaking contributions” to the field of Quantum Theory. De Broglie had several written works; some of which follow: “An introduction to the study of wave mechanics (1930) · Recherches sur la théorie des quanta (1925) · Matter and Light - The New Physics (1939) · New Perspectives in Physics (1962) · Introduction to the Vigier Theory of Elementary Particles (1963) · -
J. J. Thompson
These electrons impacted the science world because people started to think about atoms having charges and wanted to prove that there were other charges in the atom. -
Ernest Rutherford
He concluded from the ones that bounded back hit something in the atom that caused it to reflect and shoot backwards. He concluded that the atoms had a central particle called the nucleus and that when an alpha particles nucleus hits the nucleus of the gold foil it bounces back. From this experiment he concluded that most of the atom is empty space. He impacted the science world with this discovery and cause everyone to begin to understand the atom more. -
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Werner Heisenberg
Werner Heisenberg was a German theoretical physicist +philospher who was best known for his innovation in Quantum Mechanics and for his Uncertainty principle. Heisenberg was awarded a Nobel Prize for his new way of representing problems in the form of Matrices in the year 1932. Heisenberg’s Uncertainty Principle states that the position OR the velocity of a particle can be known, but not known- That is the uncertainty. -
Robert Millikan
positive or negative, or they would not go to any side. He looked through a microscope to tell which ones were one which side or if they were in the middle. This experiment showed if the atom was positively charged or negatively charged or neutral. This affected the way we looked at atoms because it proved that Thomson's experiment was correct and showed that there were more things in the atom. -
Neil’s Bohr
This revolutionized the way people think about the atom and is used widely today. -
Albert Einstein
Einstein also studied the Photoelectric effect (1921) and Brownian Motion (1905). Einstein’s breakthrough in Brownian Motion was in part to his “Pollen Grain” Experiment, in which grain of pollen appeared to vibrate under the view of a microscope- Einstein “explained that the grains were being moved by the water molecules+ atoms- providing evidence for Particle Theory. -
Albert Einstein
His works help explain the energy within atoms. Einstein’s famous formula for Mass energy equivalence in his theory of relativity, E=Mc2, simplified/condensed an incredibly complex idea into a short, easy-to-understand equation. Einstein was one of the most influential physicists of all time- he received a number of awards and acknowledgments + His name is now synonymous with ‘genius’. -
Erwin Schrodinger
“Eigenvalue Problems(Eigenvalues tell you how much variance there is in the Data in that direction)of Continuous Media”; this understanding helped him especially when he was forming his Wave Function. Unlike some other great minds of the time who were incredibly specialized in only one subject, Schrodinger excelled in/ and impacted another field in addition to Science- Philosophy. -
Louis De Broglie
Heisenberg’s Uncertainties and the Probabilistic Interpretation of Wave Mechanics: with Critical Notes of the Author (1990)” De Broglie looked into thinking more abstractly- viewing physics more conceptually and less through a physical ‘lense’. In 1924, De Broglie “proposed that just as light has both wave-like and particle-like properties, electrons also have wave-like properties.” After proposing this, De Broglie followed it up by supporting it with an equation (shown). -
Louis De Broglie
De Broglie’s work mostly falls under the category of what now is known as “Matter Wave”&” Wave Equation”. This was important to the development of our view of the atom today because the wave equation helped advance our understanding/explain how electrons work/interact within their orbits. -
Werner Heisenberg
Along with his Uncertainty Principle+ Quantum Mechanics research, Heisenberg also made important contributions regarding “hydrodynamics of turbulent flows, the atomic nucleus, ferromagnetism, cosmic rays, and subatomic particles.” Heisenberg is regarded as one of the three writers for the “foundational document of a new quantum mechanics.” -
Questions
When was Rutherford born? When did Millikan die? How did dalton's work affect the modern atom?